Google Calendar - Spend less time managing your day & more time enjoying it
Mixmax Calendar - The fastest way to schedule meetings with anyone, anywhere
Teamup Calendar - Cloud-based calendaring using capability URL, application developed in Zurich, Switzerland.
Clean Google Calendar - Makes Google Calendar look nicer & launches as a desktop app
Teamweek - A project management software to help you get the best overview. Plan fast, change plans faster!
Sunsama - Calendar and scheduling for teams