Time.is - exact time in any location
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.
World Time Buddy - Effortless time conversion and world time.
Harvest - Simple time tracking, fast online invoicing, and powerful reporting software. Simplify employee timesheets and billing. Get started for free.
timeanddate.com - Free Clock for your website or blog!
RescueTime - Time management software that shows you how you spend your time & provides tools to help you be more productive.