9 Products Powered by Unusual Means

The battery freed us from the power cord's limitations, just as gasoline freed us from the restrictiveness of our own two feet. But in the intervening years, we’ve learned how to derive energy from a number of more natural substances, including water, glass, wood and even our hands.

The gallery above includes a number of devices that can either propel us into the future or the past of energy derivation. Nevertheless, none of these products use traditional batteries or cords to power up.

From light to water to your own two hands (and — err — urine), energy is everywhere. Read more...