Tom Scott

If you travel to Greenwich, stand on the famous Prime Meridian Line -- which is marked with a physical line and a sculpture at the Royal Observatory -- and look at your GPS, it won't read 0° longitude. It'll be slightly out. Who's right? And why?

It's been all over the British news today: developer Paul Price found a bug in photo-crap-maker Moonpig's site, one that might have exposed three million users' personal information. Paul's got a great technical post about it at https://www.darkport.co.uk/blog/moonp... -- but there's no decent non-techie explanation except for the one-paragraph summaries in newspapers. It was a perfect storm of tech incompetence: here's how to avoid doing it yourself.

Despite its reputation as being a Traffic Circle of Hell, Swindon's Magic Roundabout -- like the couple of other "ring junctions" in the UK -- is a triumph of road design. Here's why it works so well.

In the 1970s, at the height of the space race, British Rail -- the government organisation that ran all the UK railways -- patented a flying saucer. How? Why? And could it ever have worked?

Yes, there are more than seven; but they include a few colours that most people can't see, too. We're going to trace a two-minute course through Isaac Newton, cataracts, Claude Monet, and the wonders of evolution.

For those of us who grew up in the age of CGI, green screen is just "a thing that computers do". But how did effects like this work before the age of pixels? With the help of some suitably shiny graphics, here's a quick summary.

Comic Relief raises millions every year to fight poverty around the world. This year, they're asking you to make your face funny for money -- so here I am, in the wind tunnels at the University of Southampton, ready to find out what it's like to stand in a hurricane. Please, if you can: donate or, better yet, fundraise yourself: http://rednoseday.com/ideas/

Thanks to the Transport Research Laboratory for letting me have a test ride on one of the Meridian Shuttles they're testing on the Greenwich Peninsula! If you want a ride, they'll be there, on and off, between March and May -- not often enough to make a special trip worth it, but if you're in the area, see if you can spot one!

This isn't going to give you all the details of how to program a quantum computer: but it'll at least explain what you're doing in the simulator! Play here: http://www.bristol.ac.uk/physics/rese... -- I don't understand it, but then I don't have a qualification in quantum physics! Thanks to Jacques Carolan, and all the team at Bristol University's Centre for Quantum Photonics -- and thanks to Tom Morris for holding the camera!

The idea of a "public road network" is a relatively modern one. After all, the US Interstate System was only finished in 1991, and UK motorways aren't that much older. What if history had taken a different turn? Let's talk about turnpikes, toll roads, and perhaps even zeppelins.

What if you could have a perfect filter for the web? Anything you'd regret seeing or reading: it's gone before you even see it. Welcome to the Bubble.

I took a trip to the University of Bristol, to have a look inside a nanomaterials lab, and to be surprised at a combination of massively expensive equipment and very basic tools... Thanks to the Bristol Centre for Functional Nanomaterials and the Chemical Imaging Facility at the University of Bristol -- and to Kate Oliver and Andy Collins!

Back in the Caledonian orogeny, 400 million years ago, two bits of the Earth's crust began to collide. The result, a long time later, was the Central Pangaean Mountains: and now, you can find their remnants all over the globe.

Don't worry: unlike last time I did a video like this, I'm not actually going to attempt to do any of these. I swore off politics a long time ago! Purdah also applies to civil servants, who basically can't do anything public for weeks. All the government departments' Twitter and Facebook accounts will be going very quiet...

In the foothills of the Dolomites, an hour or so north of Venice, lies Ai Pioppi, a restaurant that's home to an astonishing, giant, human-powered, kinetic-art theme park playground. It was designed and made by a man called Bruno over forty years, and it's free for folks who eat at the restaurant. I'll be honest: I sort of thought it was a myth. The idea of unattended, huge kinetic ride-on sculptures was surely false? There was some evidence: a very artfully-shot documentary, and some shaky tourist footage, but I couldn't quite believe that something this potentially dangerous could still exist. So on Easter weekend, when it was quiet, Paul (@cr3) and I took a road trip to try it. And it's real. It's very, very real. Watch as we try and take a somersault on the Bicycle of Death. And if you don't take the right amount of caution, it can hurt you -- although my eventual injury didn't come through any rides, but just by tripping over by running!

This weekend, the Royal Navy was offering public tours of HMS Defender, one of their new-generation Type 45 destroyers. It's an astonishing ship: about 8,000 tonnes of steel and high-tech equipment designed to defend an entire fleet against air and missile attack. There's another type of attack it's more vulnerable against, though: the sea mine. And by luck, there was a good example of mine defence docked a little way upriver...

In a fjord near Stavanger, in southern Norway, is Preikestolen: Pulpit Rock. It's known as one of the world's scariest tourist attractions, for good reason -- but despite the millions that visit it, it's pretty safe. At least, for current human values of safe. Let's talk about risk, immortality, and what it means to be human. Thanks to my friends Tim, who held the camera, and Matt, who got the shot from the boat below. Tim did manage to dangle his legs off the end: I got a photo of him, while muttering "no, no, no, no" under my breath...

The Delta Works, to the west of the Netherlands, are one of the modern wonders of the world. But there's other, lesser-known infrastructure there too: including the Rozenburg Wind Wall, on the Caland Canal, which turns a dangerous, windy stretch of canal into a much more navigable bit of water. It's a triumph of humanity over nature, and it's astonishing.

Machine translation's a useful tool, don't get me wrong. But if you actually try to use it for regular conversation, it'll fall down really quickly. Why? What makes it so difficult?

On stage at Thinking Digital 2015, I talk about angry people, livestreaming, and how nothing seems to have changed recently. Thanks to all the crew, volunteers, sponsors and technical team at Thinking Digital -- I'm using several camera angles and the audio from their livestream, plus my Periscope broadcast and a GoPro from the front row (thanks Emilia)!

In Spijkenisse, in the Netherlands, are a set of small bridges that most of Europe should recognise instantly: because they're the fictional ones from their banknotes, made real as a wonderful piece of public art and infrastructure.

One comma can make a lot of difference. Language is ambiguous -- but in some very specific ways. Here's how.

There are all sorts of theories about why a string of weird, mostly-Arabic text can crash your iPhone. I've hunted through them, summarised the ones that seemed plausible, and the first part of this is a run-down of what's going on. The second part: well, I'm going to take a punt at explaining why Arabic, in particular, causes this bug -- and hopefully we'll see if I'm right or wrong soon!

Yes, plenty of folks already know about the most complicated borders in Europe, in Baarle-Nassau (the Netherlands) and Baarle-Hertog (Belgium). But why did we end up with this particular system? Why do we have nations in the first place? Most historians would say it goes back to something called the Peace of Westphalia, many years ago...

Kids learn languages really easily, don't they? There's this thing in your brain that just works it out -- but it switches off when you're an adult. Right? Well, maybe. But it's not that simple.

There aren't many paternoster lifts left in the world: they're inaccessible, tough to maintain and a bit more dangerous than a regular lift. But some of them still exist: so if you're ever nearby, do stop by the University of Sheffield's Arts Tower and have a ride up and down. Just don't go over the top. Thanks to Chris Dymond, who was my camera operator for this trip to Sheffield!

Some languages have longer words than others -- but that's not just a simple choice. There's a lot of different ways to mix up morphemes, even if they all mean the same thing in the end.

In a disused quarry at Harpur Hill, near Buxton, there's a bright blue lagoon. It looks like a perfect place to cool off in summer. And it is, if you enjoy skin irritation and fungal infections. But the strange thing is: I arrived expecting to find it black, not blue...

"Word Count" is going to count plenty of things that aren’t words too -- and it doesn’t get to a more fundamental question: what actually is a word?

There's a strange avenue of trees in Richmond Park, ten miles from St Paul's Cathedral; and an odd, wedge-shaped skyscraper in the city. At the New London Model, at the NLA Galleries at the Building Centre, I explain both of these. London is going vertical: but there are quite a few places where tall buildings aren't allowed, and here's why. Thanks to Dan W on camera, and to the team at the New London Model!

You might have heard of the Svalbard Global Seed Vault: it's called the "doomsday vault", the backup of last resort for if the apocalypse happens. Except... well, perhaps that's a bit too dramatic.

(EDIT: Of all the things not to fact-check! It's UTC, not UCT. Which is short for Coordinated Universal Time, because reasons. Well, that's embarrassing.) There's a leap second tonight! And while there's not the Y2K-scale of disaster being predicted for it, there are probably going to be a few problems. Here's why computers have trouble with something that should, in theory, be pretty simple.

In Svalbard, in the Arctic Circle, there's a sundial that works 24 hours a day! Sort of. When it's sunny. Which it wasn't. Basically, don't rely on this for telling the time. CORRECTION: "solstice", not "equinox".

I had an enormous amount of B-roll footage of Svalbard that I couldn't use, and the internet had a lot of questions about how to get there. Time to solve both those problems in one go!

Welcome to Svalbard, a group of islands in the High Arctic, north of Norway; the one place on the planet where carrying a gun is a legal requirement, and for a very good reason.

Robert Llewellyn is lovely! He agreed to drive me at 135mph for this video, and I was in a remote controlled car that he drove over on his channel.

With many, many thanks to all the team at DP World London Gateway (http://londongateway.com - http://twitter.com/LondonGatewayUK )! This isn't a sponsored video: they just went above and beyond to make sure this looked good, and I'm so grateful to them.

The biggest uninterrupted indoor space on the planet, Tropical Islands Resort ( https://www.tropical-islands.de/ ), sits on an old airfield in Germany. How on earth could anyone afford to build something that big... and then use it as a waterpark? Well, the story's a bit more complicated than that. (And full disclosure: this isn't a sponsored video, no money's changed hands, but Tropical Islands were happy to let me in free and give me a ride up on their balloon. I'm grateful to all the team there for a fantastic day!)

Deep in rural Ukraine sits what was once the V.I. Lenin Nuclear Power Station. Now, it's the site of the worst nuclear disaster in human history: and one that still needs to be contained, thirty years later. How do you deal with something that'll be this toxic for so long into the future?

In the abandoned theme park of Pripyat, I have a banana. For scale. Let's talk about the Banana Equivalent Dose. Thanks to Ashley Shepherd for the drone footage

Here's the behind-the-scenes video from Chernobyl week, where Paul (@cr3) and I answer how we got here, and what it's like -- while you see all the B-roll footage that I couldn't fit into the regular videos!

Thanks to Ashley Shepherd for the drone footage - see the full video on his channel here: • 4K Drone Footage from Chernobyl and P... This is the Duga-3 array, inside the Chernobyl Exclusion Zone. It's an incredible piece of Soviet engineering, capable of sending radar pulses so powerful they could see over the horizon. Which, when you think about it, is more complicated than it might initially appear...

There are only a few transporter bridges still working in the world. What are they for? Why weren't there more of them? And why don't we build them any more? Those answers and more, from an unsettlingly high position fifty metres above the River Usk.

Hovercraft were the future. So what went wrong? I had a brief stop on the Isle of Wight last week, and had one chance to get this video. Turns out hovercraft are loud, and you shouldn't stand too close behind one. Correction to this video: a comma got moved in the script. The section about Concorde should read "after one of the planes crashed, in 2003 the airlines decided...". Punctuation's important!

For a few weeks every year, the road through the abandoned village of Imber, in the middle of the military firing range of Salisbury Plain, is open to the public. How can the government seize and evacuate an entire village? And would it be possible now? Thanks to Paul (@cr3) for his camerawork!

A guide for the newly empowered, courtesy of the Superhero Help Academic Foundation Trust, Education Division. Sure, you could jump a few places and fight crime: or you could take over the world. Thanks to YouTube Space London, who offered me time on their science lab set -- and thanks to Matt Gray (http://mattg.co.uk - @unnamedculprit) who directed the shots! Oh, and if you want to see teleportation in fiction done well, have a look at Steven Gould's Jumper series -- the later books really start playing around with physics in fun ways, like building a... well, I'll leave that for you to read. (Amazon UK affiliate cash-in link: http://amzn.to/1gYOEZx )

Time to learn about graveyard spirals, while trying not to be in one! I was so far outside my comfort zone for this. Thank you to Bruce Duncan from the Edinburgh University Gliding Club, who got me safely up and down again, and to Alistair Hammond from the Loughborough University Gliding Club, who managed to talk me into experiencing serious G-forces for the first time in my life! We launched from Bicester Gliding Club. I'd seriously recommend giving it a go if you can!

Thanks to the Environment Agency for letting me film! The invite came via my friend Paul Curry - you should read his write-up, which features a few more details about the boat, its controls, and hunting for eels

On a windy day in Gloucestershire, I find one of the few parts of the once top-secret GPSS aviation fuel pipeline (now called CLH-PS after privatisation) that pokes above ground, and explore the balance between secrecy and safety.

With many, many thanks to the Royal Navy and everyone at HMS Excellent! http://royalnavy.mod.uk How do you train sailors to save a sinking ship? Sure, you can teach them the theory, but there's no replacement for having to hammer softwood wedges into deck and bulkhead splits that are spraying cold, high-pressure water in your face. At HMS Excellent in Portsmouth sits Hazard, a Royal Navy Damage Repair Instructional Unit (DRIU). Every Navy recruit who's going out to sea will have to go through something like this -- and on a much harder level than we did! But then, they'll have had months of training and teamwork beforehand...

In the cloisters of University College London sits noted philosopher Jeremy Bentham: the man who asked to be dissected, stuffed and preserved in his will. WARNING: This video contains a really gross shot of his preserved, severed head.

This is the most ridiculous thing I've built in a long while: a full-size, real-life emoji keyboard, made of 14 keyboards and over 1,000 individually placed stickers. And yet, it's got everything from Unicode 8 -- but not yet the candidates from Unicode 9. I might need another keyboard for them, next year.

In the news today: a link which, when moused over or clicked on, crashes Google Chrome. It's a heck of a bug: but how does it work, and what does it have to do with "null-terminated strings"?

Here's the behind-the-scenes "how I made the emoji keyboard" video! If you haven't seen the original: • Real Life Emoji Keyboard! But the thing is, the truth is basically just "I bodged some stuff together". Which gives me the opportunity to tell some stories...

The Falkirk Wheel sits between Edinburgh and Glasgow, in the southern parts of Scotland, and it's the world's only rotating boat lift. There's some very clever design going on here -- and some physics that goes all the way back to Ancient Greece.

Thanks to all the folks at the Institute for Computational Cosmology! You can find out more here: http://icc.dur.ac.uk/Eagle/

Deep in the Essex countryside lies Kelvedon Hatch, and the Secret Nuclear Bunker that's now an off-beat tourist attraction. Inside, I met up with Greg Foot from the BBC's Brit Lab, and discovered the rather optimistic 1980s plans for tracking nuclear fallout, and helping the survivors of a nuclear war... if there were any.

Under the Elbe river in Hamburg, Germany, lies the Old Elbe Tunnel in St Pauli. Like early 20th century tunnels around the world, it has lifts or stairs to take you down and under the river. But this is on a whole different scale to those you might have seen elsewhere...

In north-west Germany sits Bielefeld, a city complete with castle, cathedral and citizens. Just one catch: according to something that's half urban legend, half in-joke, it doesn't exist. Let's talk about belief and Bielefeld.

Goalball was invented after World War 2 to help rehabilitate blinded ex-servicemen. Nearly seventy years later, it's now a Paralympic sport, where every player has a full blindfold and puts themselves deliberately in the way of a very heavy ball going at 25mph -- and in world-class games, anything up to 60mph. Do try this at home - just with the right safety equipment.

Trademark rights are an interesting thing. You can see this thing from all over the city of Los Angeles: but if you want to use it for anything commercial, well, then you're going to start having some trouble.

Los Angeles needed water, and lots of it. It still does. And that water comes from the LA Aqueduct, masterplanned by William Mulholland. The end of his career, though, wasn't such a triumph. This is the story of the St Francis Dam, and the collapse that stopped Los Angeles from taking over an entire valley. CORRECTION: It actually held back 47 million tonnes of water, 470 times more than I said. I mistook the dam volume for the reservoir volume when researching! Thanks to Josh for pointing that out.

The Rosetta Stone is one of the most famous archaeological finds in history: and it was the key to cracking Egyptian hieroglyphics. And while it took scholars years to work it out, there was one clue in there that helped unlock everything that followed. After hours in the British Museum, I went to explain...

Welcome to Galco's Soda Pop Stop, and the wonderfully knowledgeable John Nese. Thank you to John for his time, and to all the team at the Soda Pop Stop! You can visit them here: http://www.galcos.com/ In Highland Park, in Los Angeles, sits something that most business analysts would say couldn't exist any more: an independent store selling soda pop. 700 flavours of it. There was so much I couldn't include in this thanks to my dodgy camerawork -- the create-your-own soda section, John's absolutely perfect recommendation for a soda I'd like. But hopefully I got all the important parts! If you're ever nearby, do stop in.

In the desert of California, we're flying drones. It's safe out here: but just how many people are flying near airports? The answer: a lot.

Mevea Simulation sit in Lappeenranta in Finland, and they may well make the greatest industrial simulators on Earth. I had to go check them out. And no, this isn't a sponsored video: I found out about them, emailed them out of the blue, and they were nice enough to agree to show us around and use their contacts to get us to the steelworks! (See the behind the scenes video for more!)

In Europe, you're legally protected from "automated decisions". The US Army, in a recent report, may have to take issue with that. What's the battlefield of the future going to look like? And why is there a tank painted bright blue in the middle of London?

In 1987, a German student wrote CHRISTMA EXEC - a virus whose basic mechanisms still work if you port them to today's desktop computers. Why haven't we changed in nearly 30 years? And what could we do instead? Merry Christmas to all, and to all a good night.

On Christmas Day, someone at Steam changed a setting and brought down their whole games platform. I wasn't expecting to do a video this Christmas, but when enough people tweet me, it turns out I can be convinced... (I should note: while Steam have officially confirmed "a caching problem", I've got no privileged information about the specifics. It's possible (but unlikely, I think) this was a misconfiguration at Akamai, or a bizarre server bug that happened to exactly match a much more likely caching misconfiguration error!)