But WiTricity, based in Watertown, Mass., is thinking big. Its technology—involving a plug-in coil that creates a magnetic field, which in turn powers objects as far away as 8 ft. (2.4 m)—has been tested on Toyota electric cars (with charging mats), Intel PCs (with charging pads) and more. Within 10 years, says CEO Alex Gruzen, rooms could be wired so that all appliances—lamps, TVs, stereos—pull power from a central charging base.