No one mentioned about Time Doctor?
I use that time tracking software alongside my team of VAs, designers and other freelance workers.
It works really well for tracking our work hours and monitoring our computer activity. Productivity at its best. :)
Here are few good time tracking apps to serve the purpose with some good words about them.
http://lifehacker.com/5362829/five-best-time+tracking-applications
Hope you find it helpful.
WorkTime is fully automated Internet monitoring software. I think it is the best time tracking software. Thanks!
Five Best Time-Tracking Applications
1. Project Hamster (Linux, Free)
2. RescueTime (Windows/Mac, Free)
3. SlimTimer (Web-Based, Free)
4. Manic Time (Windows, Free)
5. Klok (All platforms with Adobe AIR, Free)