Time Tracking for Freelancers - A simple, fully integrated time tracker for freelancers
Klokki for Mac - Rule-based automatic time-tracking
Hours - Boosting productivity through live, virtual co-working.
Futuramo Time Tracker - Futuramo Time Tracker is a time tracking solutions designed for freelancers and teams.
Time 2 - Stay focused and crush procrastination
Toggl - Toggl is an online time tracking tool. It features 1-click time tracking and helps you see where your time goes. Free and paid versions are available.