Just when you thought a unicycle was a small as you could - so far as cycles go - along comes the wheel. I know it's a waste of time to re-invent the wheel, but evidently it's been done. So if a two or three wheeled bicycle (otherwise known as a tricycle) is too pricey for you, and a unicycle is still beyond your means, behold . . . the wheel! With the money you save you can probably pay for your medical bills when they pop a wheely.
BTW, i try to check out the sites these videos promote (before I pass them along) but this one's is in French. So if you speak French and these guys are cursing about how good their wheel is, I apologize.