Remember how computers were supposed to eliminate paper in the office?  Now we have more paper than ever thanks to computers.<p>With self-driving cars people can have their cars out running errands for them during the day.  Need to pickup something two hours away? No problem, send your car to get it while you are at work.  The car that was sitting idle in the parking lot is now out on the road during the day.<p>By eliminating the driver the number of cars on the road might increase dramatically.