The promise of personal access to the vast resources of the Internet seems tantalizing when wielding today’s powerful PCs. But for portability, battery life is still limiting. This research may serve to power the increasingly wired yet mobile individual.

“Rome et al have devised a machine that recovers energy that is otherwise wasted. They

have modified a backpack by introducing a vertically moveable weight that

rises about 5 centimeters with each step and then turns a gear as it falls.

This device can be used to recover some of the energy used in carrying

supplies–a load of 38 kilograms produces up to 7 watts of electricity,

compared with about 20 milliwatts from shoe-based devices.”

http://www.sciencemag.org/cgi/content/short/309/5741/1725

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