It's hard to imagine software giant Microsoft in the role of David, but up against the search Goliath Google, the casting fits. Fortunately, the 48-year-old Bing chief knows how to overcome entrenched regimes. After enduring Mao's Cultural Revolution in his native China, Qi Lu earned his doctorate at Carnegie Mellon University, then rose to lead the search and advertising business at Yahoo. In Redmond, Washington, the holder of 20 U.S. patents is applying his inventiveness to a company desperate for a spark. Spurning the antiquated practice of releasing new updates every couple of years, Lu is creating an environment where live-cycle updates and product improvements are constant. Bing's share of the search business is still only about 12%, but if anyone can turn a pebble into a deadly stone, Lu is the man.