Back in 2004, the Pentagon offered $1 million to anyone who could build a car that drives itself 142 miles across the desert. The best one made it 7.4 miles before it got stuck on a dirt berm and its front tires caught fire. Paul Graham's car just drove him from his driveway to a parking space at the gym without anyone touching the controls. That 2004 race cost DARPA $13 million to run, and the teams spent an estimated four to five times that on their entries. Nobody finished. So in 2007 the…