The Museum of Unworkable Devices

*A really beautiful site here. It's old, but these magnificent follies are timeless.

http://www.lhup.edu/~dsimanek/museum/unwork.htm

"Whatever you try, geometry stands in your way every time. Try such things over and over, and eventually you may discover that the geometry of the universe, and the physical laws constrained by that geometry are all conspiring to do one thing: absolutely prevent the possibility of a perpetual motion machine. This may be the most profound statement one can make...