I came across this video the other day and I'm completely hooked.
Some information I came across these things is from flixxy stating:
Powerbocking is the act of jumping and running, much like parkour, with elastic-like spring-loaded stilts.
For some it is an extreme sport, for others it is a form of exercise or even a means of artistic expression. The use of the stilts to perform extreme jumping, running and acrobatics is known as 'Bocking' or 'PowerBocking' after the inventor Alexander Böck.
There are 3 main companies producing powerbocks for hobbyists: Fly Jumpers, PoweriZers and Pro Jumps.
I can't think of a reason not to do this. Well, except that on Amazon one reviewer says that if you hit a pebble you fall on your tookus, and you can't stand still on them without holding something. But as someone who had Rollerblades within months of them coming out (best parents ever) I am all over these!
Now. . . where am I going to get $300?