Seen on Ars:
Engineers from Stanford and Berkeley Universities have figured out how to make radios the size of an ant, which have been created specifically to serve as controllers and sensors in the Internet of Things.
The radios are fitted onto tiny silicon chips, and cost only pennies to make thanks to their diminutive size. They are designed to compute, execute, and relay demands, and they are very energy efficient to the point of being self-sufficient. This is due to the fact that they can harvest power from the incoming electromagnetic signal so they do not require batteries, meaning there is no particular lifetime associated with the devices.