Wireless charger and power supply

It may sound futuristic, but Powercast's platform uses nothing more complex than a radio--and is cheap enough for just about any company to incorporate into a product. A transmitter plugs into the wall, and a dime-size receiver (the real innovation, costing about $5 to make) can be embedded into any low-voltage device. The receiver turns radio waves into DC electricity, recharging the device's battery at a distance of up to 3 feet.How it works: (1) The transmitter plugs into the wall socket and broadcassts safe, low-power radio waves. (2) The radio waves change their requency as the bounce off objects and walls. (3) Tiny receivers in your devices "hear" frequencies around the original one, capturing upto 70 percent of the radio signals energy. That energy is converted into DC electricity.

Source: money.cnn.comAdded: 2 April 2007