Doc Mécano, AKA Philippe Moisan from Québec City, is a master of other-worldly ramp walkers and other mechanical toys. He works to interest kids in science and tools through programs in schools and libraries. I thought ramp walkers would be very hard, but he says simple ones can be made from common bendable materials. Check out his other videos, too.
Mysterious, Kinetic, Noisy, Do-It-Yourself Science Projects that Entice Scientific Investigation