http://www.youtube.com/watch?v=qaJx2YCd8O4&feature=grec

It's a motorcycle. The guy's actually pretty amazing, but the thing looks like a bmx bike. What is he riding and where can I buy one for cheap?

 

Google "moto trials bike"
I have seen some insane rock climbing vids out there with these bikes.

 

+1 Trials bike

I've seen a couple of organized trials runs in the clay hills where my family used to go to ride dirtbikes in N. Fl. They use speed and momentum to traverse some ridiculously steep rock and clay faces through trees and such. Pretty impressive stuff.