You no longer need billions of dollars and a secret dream to take over the world like Elon Musk to build an electric car. If you can find a pair of round magnets and a AA battery that isn't already dead, you can build this incredibly simple electric vehicle that's better than watching TV.
You might be wondering how this contraption can roll around all on its own without an electric motor but it's there; it's just invisible. This simple assembly is what's known as a homopolar motor which places a conductor inside a magnetic field to generate forces perpendicular to that field.
Did you notice that all the footage of this simple electric car was shot with it working on aluminium foil? That wasn't laid down just to make the video a little more flashy. The foil road actually serves as a conductor between the two ends of the battery. And when it ends up mixing with the magnetic field generated by the two magnet wheels, there's enough force to push the entire thing along at an impressive clip.
So can we cover all the world's roads in aluminium foil and just build ourselves simple electric cars to drive around? Probably not. But as DIY science experiments go, this one is pretty easy with a wonderful payoff. [YouTube via Kottke via Digg]