http://www.etotheipiplusone.net/?p=804
I actually did a lot of planning into building a system like this, but I figured I'd only be able to recoup the cost of the build if I could sell some of them, and since the whole concept is patented six ways from Sunday I gave up 
The differences I see here are that this guy has manual throttle control and much smaller batteries and wheels than I would have considered (my batteries would have been stored in a small backpack along with the automated motor controller, with wires running to the blades. This allows for bigger, better cooled batteries, more flexible power options, and lighter blades with bigger wheels). Also, no brakes whatsoever 
guess you just slide to stop...I'm surprised he didn't at least attach some conventional roller blade brakes.
But still, awesome work. This makes me want to go through with my own plans more. The motor-in-wheel design has some potential, it makes cooling a much bigger problem but saves on complexity and weight vs. a belt or chain drive.
