“A novel type of wireless device sends and receives data without a battery or other conventional power source. Instead, the devices harvest the energy they need from the radio waves that are all around us from TV, radio, and Wi-Fi broadcasts.
“These seemingly impossible devices could lead to a slew of new uses of computing, from better contactless payments to the spread of small, cheap sensors just about everywhere.
“‘Traditionally wireless communication has been about devices that generate radio frequency signals,’ says Shyam Gollakota, one of the University of Washington researchers who led the project. ‘But you have so many radio signals around you from TV, Wi-Fi, and cellular networks. Why not use them?'”
Read more (and watch the video demo) here.