The thought of thousands of autonomous vehicles flying down our highways might be a frightening one, but it could also be a permanent solution for traffic safety. The Eno Center for Transportation claims that the proliferation of self-driving cars could cut down on vehicle-related injuries by up to 90% while saving the U.S. economy around $450 billion annually. According to the Eno Center, a vast majority of accidents occur because of human error, and more than 40% of wrecks involve drugs, alcohol, distraction or fatigue. Remove these factors from the equation and the roads quickly become much safer. Of course, the technology behind autonomous vehicles is still being perfected, so it could be years before this vision of the future is even feasible, much less financially viable.