This is the simplest electric motor I've ever seen. Watch the movie to see how fast it spins. Link
Reader comment:
Tom Radcliffe says:
I've gotta tell you, the website linked on Boing Boing about how to make a homopolar motor in 30 seconds is false. It actually took me 92 seconds from reading the blog to having a spinning motor (most of which, I admit, was taken up in finding, cutting and stripping the wire.) Weirdly, I've had a drywall screw sitting on my kitchen counter for a few weeks, so that part was easy.
This is by far the coolest do-it-yerself project I've ever seen — I've known about homopolar motors for a long time, but never thought it would be this easy to build one.
Many thanks!