A new kind of cool

The exhibit hall was buzzing like a high school science fair. At this year's Energy Innovation Summit, hosted by the U.S. Department of Energy's Advanced Research Projects Agency (ARPA-E), several hundred inventors and entrepreneurs had propped up posters to show off their bright ideas. At one table, a couple of Ph.D.s were grinning as if they'd already taken home a trophy. In a way, they had-their company, Phononic Devices, had made the most of a US $3 million ARPA-E grant it won in 2009, parlaying it into $10 million in venture capital money to commercialize its technology.