SolePower shoe is a device that fits into your shoe that charges your phone while you walk. It is capable of charging portable devices such as cell phones, MP3 players, and GPS units on run.
The mechanism involved is that an electrical wire runs from the SolePower insole, via your shoe and out through the laces. This wire connects to a portable battery that can be strapped to the side of the shoe, or around your ankle.
While walking the insole converts the energy from each of your steps into usable electricity, which is transferred to the portable battery. The charged battery can be transferred to your device on completion of the walk.
Right now, the sole prototype is rated to last 100 million steps. The ultimate aim SolePower is to develop a shoe that charges your iPhone while you walk – 2.5 miles for a full charge to be precise.