At Box.net, there is such a thing as a free lunch. There's also such a thing as a free dinner. Box.net CEO Aaron Levie founded the company just six years ago, but in that time he's built the company into a mini-empire based on two principles: work hard and play hard. Levie describes the culture as "very high energy" and also "very collaborative." The eclectic office includes swing sets, ping-pong tables, a piano, as well as a basketball hoop. "We're very oriented around high performance and high output," he says. "But the idea is to build an organization that makes it fun to be here."