"Yo-Yo wireless mouse concept charges with the flick of a

 wrist, saves your back"

Yo-Yo Mouse
We've seen plenty of round mice, including Apple's infamous puck, and many devices that derive power from a yo-yo-like pull string mechanism. So we're not quite sure why we've never seen those two concepts married before. In retrospect, a wireless mouse charged by the kinetic energy of using it as a yo-yo seems like a painfully obvious idea. As an added bonus, this tiny pointer with an LCD battery gauge makes you get up every so often and get your limbs moving -- thus saving you from chromic back pain. Huzzah! Of course, there's no guarantee you'll ever actually see one of these on shelves. Check out the source for a few more pics.

Source:http://www.engadget.com/2011/12/14/yo-yo-wireless-mouse-concept-charges-with-the-flick-of-a-wrist/