I started using Rescuetime today. It seems to be a pretty sophisticated tool for time tracking and requires virtually no work to set up. This ties back to my post two weeks ago about how to boost productivity, which outlined several ways to track the places that time goes, so that you can later make a judgment about the best way to budget or manage time for improvements in productivity. This tools seems on the surface to be a much easier way to accomplish the task.
I'll keep you posted with a full review at a later date, but please post a comment if you have any experience with the tool.