If you live and work in Los Angeles and have an average commute, you spend 72 hours a year in traffic. That's enough time to read War and Peace once, get through Wagner's The Ring Cycle almost five times, or watch the entire Lord of the Rings trilogy almost eight times. The page includes stats for other cities too.
Update: A closer read, a bit of arithmetic, and several emails have convinced me that the 72 hours is not the overall commute time but the time spent sitting motionless in traffic. (thx, everyone)