Invention - knee generator for your cell phone

In the never-ending quest to power cell phones and iPods on the go, we now have the knee generator:

Human dynamo: How energy from your knees could power an Ipod

One thing that makes this invention interesting (as described in the video below) is that it gathers power from only part of the stride, meaning that it doesn’t require much extra effort on your part to power it:

The article puts it this way:

The knee brace harvests energy lost when someone bends their knee after swinging the leg forward to take a step… “We believe that when you’re slowing down the knee at the end of swinging the leg, most of that energy is just wasted.”

[[[See previous invention]]]