One wheel bike

[Leisured]

Ingenious bike. Seems to work like a Segway, in that it balances itself.

http://www.youtube.com/embed/Z1YoCfm7nxU?feature=player_detailpage

[rubybeth]

I thought it was going to be a unicycle. A uni would be better exercise. :)

[AlmostIndependent]

I want to learn to ride a unicycle. Totally impractical but interesting.

[StarswirlTheMustached]

I once someone commuting downtown by unicycle. Hilariously badass, and you don't have to worry about locking it up.

[rubybeth]

I know how to ride a unicycle.

It's actually very practical compared to a bike--it's smaller, lighter, and you can store it in your garage or office or trunk a lot easier. It is more work to ride than a bicycle (no coasting) so even better exercise. And, I'm guessing a nice uni is cheaper than a nice bike. No chain maintenance, just tire, pedals, and a seat.

I never thought of it as being "hilariously badass," more like "insanely geeky."

[Spork]

I remember a previous version of the one-wheeled motorcycle.  It worked great up until the panic stop, then hilarity ensued.  (This one doesn't seem to have the top speed and is a totally different design than the one I speak of.)  It's definitely cool and a head turner.