Recharge your Phone by Shaking it? Incredible Technology

U.S. researchers say they are working on a new cellphone charging
system that turns movement into energy, allowing a phone to be
recharged by simply shaking it. Researchers at Virginia Tech are
designing an emergency onboard charger that draws energy from a common
piezoelectric material that can convert vibrations into energy to
power a phone, NewScientist.com reported. Vibrating the material-zinc
oxide-produced an electrical current at about 50 millivolts, they
said. The vibrations could come from finger taps on the phone's
keyboard or by shaking the phone, they said. While it wouldn't produce
a great deal of power -- not nearly enough to continuously operate the
phone --it would be sufficient for an emergency situation, researcher
Shashank Priya said. "In an emergency you could just shake your
cellphone for a few minutes to get enough power to make this one
important call," he says.
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