A team at the University of Florida led by electrical engineer Kenneth O has built a tiny antenna that can send a radio signal across a room. Only three millimeters long and 100 micrometers wide, the antenna is the first of its size with so great a range -- about five meters. The tiny antenna is an important step toward O's goal of building an entire radio transceiver on a single microchip. The most likely applications for such radios, he says, are in cheap, robust sensor networks for security systems or for monitoring the safety of bridges or buildings; the radios would send data wirelessly from the sensors to a central monitoring computer. And one company has approached O about using the radios to make interactive toys. He hopes to have built prototypes of complete on-chip radios in about two years; in the meantime, his team is working to improve the antennas' range to at least 20 meters.