The number one benefit of working at this small, 45-person company, according to its employees, is that they get paid to play their favorite game in the world: a high-tech, GPS-based treasure-hunting adventure game known as geocaching. And at Groundspeak, which created the Web framework and mobile applications for a game played by 4 to 5 million people worldwide, the "official" benefits aren't too shabby, either. They enjoy 100 percent coverage of medical, dental, vision, and life insurance, matching 401(k), free gourmet lunch three times a week and mountain lift ticket reimbursement for all the skiing and snowboarding their hearts desire. "When even our insurance company tells us we have some of the best benefits in the city," one employee says, "you know you're working at a star company." And speaking of stars, their office in Fremont, "the Center of the Universe," happens to be the center of the geocaching universe as well. "Everyone that comes to visit us from all over the world loves us!" says one staffer. "It's like being a geocaching celebrity just working here."