Link: Turning radio waves into power (with circuits printed on paper)

    <img height="200" width="300" src="https://blog.davidcantatore.com/wp-content/uploads/2011/07/ga_tech_sensors.jpg" />

Researchers at Georgia Tech have found a way to harvest energy from electromagnetic waves in the air. The harvesting devices are produced using an inkjet printer and can collect small amounts of power from a wide band of frequencies—everything from FM radio up to radar.

Via Ars Technica http://arstechnica.com/science/news/2011/07/new-devices-convert-large-variety-of-electromagnetic-waves-to-power.ars