General Motor's top-selling 8 cylinder, 6 liter Chevy Silverado gets a tree-hating 13 miles per gallon driving around the streets of San Francisco. Accelerate too hard in one of these babies and the atmosphere might just whip up another Katrina right then and there. GM's top seller: It's a monstrosity. It's a perversion of engineering. It's paying Silicon Valley's bills. According to ComScore, General Motors bought 1,687,065,000 pageviews in January 2008, leading auto manufactures online. Toyota, which manufactures Sergey Brin's favorite, the sippy-cup Prius, only shelled out enough to reach about 60 percent as many unique visitors.