Nobody has stumped more Googlers than Wei-Hwa Huang. When the 32-year-old software engineer isn't working on the undisclosed project he's doing for Google, he moonlights as a puzzle designer. In 2004 the four-time World Puzzle Champion helped design the mathematical riddle that Google famously posted on a billboard along Highway 101 in Silicon Valley to attract high-I.Q. job applicants. In December, Huang launched Engineering Appreciation Day, during which Googlers competed in a 16-puzzle contest. And last summer, Huang hosted a puzzle hunt that had competing six-person teams running around the Googleplex all weekend solving problems. "I asked Sergey [Brin, Google co-founder] if it was okay, and he said, 'Sure. Just clear it with security,' " Huang recalls. "It was like the Amazing Race, except the puzzles were much harder and the physical challenges much easier."
Last updated January 22 2008: 8:01 AM ET