Alas, you can leave that cumbersome power cord at home. Imagine charging your mobile phone anywhere you are simply by walking. University of Wisconsin-Madison engineering researchers Tom Krupenkin and J. Ashley Taylor have developed an in-shoe system that harvests energy by walking. Currently, this energy is lost as heat. With their technology, however, they claim that up to 20 watts of electricity could be generated, and stored in an incorporated rechargeable battery. Continue reading on Gizmag. Image from Gizmag.