For moving its users to get healthy. The nifty little clip helped pioneer the now booming fitness accessory, both in its functionality of tracking user's steps, sleep, and giving them the tools to self-report their diet and in its slick, unobtrusive design. "For hardware to succeed, it has to disappear into user's lifestyle," says CEO and cofounder James Park. Users have taken more than 80 billion steps since Fitbit's launch, he says, enough to go from Earth almost to Mars. The device is now in 3,000 retail outlets, including REI and Brookstone, and Fitbit is attracting corporate customers as well. Companies such as AutoDesk are now deploying Fitbit in the hopes of inspiring greater activity and preventing expensive health problems.