Excitement is building in the world of car tech as the 2007 DARPA Urban Challenge approaches. The event, which is the third and most demanding to date in the DARPA Challenge series, requires driverless vehicles to perform mock military supply missions completely autonomously. Over a 60-mile course, the robotic cars will be required to merge into moving traffic, navigate traffic circles, negotiate busy intersections, and avoiding obstacles. Thirty-five teams will compete in the Grand Challenge semifinals taking place between October 26 and 31, with 20 vehicles going on to compete in the final race on November 3. Check out our roundup of a selection of semifinalists, including teams from Stanford, Carnegie Mellon, and MIT.