It may sound like a spectacle worthy of a Mad Max sequel, but it will be a real test of real technology. Sometime in 2004, robots will drive the roughly 400 kilometers from Los Angeles to Las Vegas. Competing in a combined on- and off-road race across deserts and mountains, they'll be advancing the technology of autonomous vehicles and vying to clinch a $1 million cash prize.

Robotic-vehicle contests aren't new, but this one, cooked up by the U.S. Defense Advanced Research Projects Agency (DARPA), could be the granddaddy of them all. That's because the route is so long and covers such a variety of terrain, and especially because humans won't be allowed to help via remote control. (They may, however, follow closely behind for safety.) Until now, contests among autonomous vehicles have been confined to small, closed courses.