Neil Gershenfeld thinks every light switch, power outlet, doorknob and thermostat should be on the Internet. That way, says the director of the MIT Media Lab's new Center for Bits and Atoms, everything from climate control to security could be coordinated through a single Web-based interface. Such a system would simplify both construction and building management by doing away with the separate, incompatible control technologies currently needed to keep a large building comfortable and safe. What's more, he says, embedding computing power in all a building's systems and components could offer unprecedented flexibility and efficiency. Reconfiguring an office space, for example, would no longer mean an expensive and time-consuming rewiring job; switches, light fixtures and other components could be moved around on power tracks and reprogrammed at will. But there's a catch. "The Internet, as we use it now, doesn't work for every light switch and outlet," Gershenfeld says. Standard networking technology is too expensive and complicated for such massive deployment. So Gershenfeld's team is developing cheap, simple Internet devices able to network themselves with a minimum of human intervention. Technology Review senior editor Rebecca Zacks got a look at the technology in Gershenfeld's lab, where he demonstrated a whole new way to turn on the lights.