The Trikke is a machine you ride and propel by wiggling your body in a way that's Zen training on three wheels. It puts into direct use the conservation of angular momentum -- if you carry a mass through a turn around a center with a radius that decreases while you're turning, then your linear velocity will increase. You move the Trikke by leaning and 'S-turning' your way through a succession of these turns. The Trikke manages to turn all this physics into a fun ride as well as a no-impact aerobic workout (good for aging skeletons).

<i>Read about this yesterday at cool tools.. looks awesome