An Alternative to Congestion Charging?

I knew that the Chinese government was restricting automobile traffic in Beijing during the Olympics, but I didn't realize how they were doing it: by allowing only even-number license plates one day and odd-number plates the next. An elegant-seeming solution, though obviously there are enforcement issues and it's class-biased (wealthy people own more than one car, so they can just use different cars for different days). Has this been tried anywhere as an alternative to congestion charging?