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.
RescueTime - Time management software that shows you how you spend your time & provides tools to help you be more productive.
Hours - Boosting productivity through live, virtual co-working.
Time 2 - Stay focused and crush procrastination
Futuramo Time Tracker - Futuramo Time Tracker is a time tracking solutions designed for freelancers and teams.
Timepal Pro - A timer that tracks your time automatically