TimeDriver isn't a shared calendar or simple meeting scheduler. Rather, it is a free service that lets you add a self-service scheduling link to Web pages and e-mails so people can book your time without conflicts and manage events on your electronic calendar.
TimeDriver.com, beta
TimeTrade Systems Inc. 100 Crosby Drive,
Bedford, MA 01730
781-541-5800
Category: Appointment scheduling software

Pros:
Simple to setup and use, free of charge and feature rich
Appointments can be offered via email or Web pages

Cons:
Outlook users need to be online to sync their appointments and busy time for scheduling to work well
Negotiated group meetings are better handled with other services

Price: Free
Requirements: Works with IE, FF, and Safari on both Mac and Windows
Integrates with Microsoft Outlook (plug-in required) and Google Calendar.