Knee brace that generates electricity from walking

This is exactly the kind of thing we need to be developing. A research team at the University of Michigan recently developed this knee brace that can harness the kinetic energy or a person walking or running. This innovation is perfect - people have to walk places anyway, and i know i personally jog at least three times a week. And from my experience walking around the park, lots of other people do to. There is so much energy simply let loose in the universe almost every time we do anything - if we could actually harness it all, we would probably never need to dig another oil well again. While the ability to completely harness every calorie we expend is not quite here yet, this knee brace is a very good step in the right direction. The next one is a stationary bike or elliptical that harnesses people energy at the gym. These have already been invented - I have no idea why gyms arent already buying them - they would never have to buy another ounce of electricity again!