Mozilla Thunderbird is an open source mail client developed by the Mozilla foundation that can can be extended to include an address book, a calendar that allows accessing shared calendars from the web, a feed reader that can subscribe to RSS and Atom feeds and a news reader that makes it possible to follow news group discussions.

Mozilla Thunderbird is available for Windows, Mac OS X and Linux. 

Related Products to Mozilla Firefox

• Mozilla Firefox

Alternatives to Mozilla Firefox

• Microsoft Outlook
• Novell Evolution
• Apple Mail and Apple iCal

The Mindquarry Collaboration Server integrates with Mozilla Thunderbird by allowing the subscription of task lists in Thunderbird and the ability to track changes using ATOM feeds and the opportunity of sending and receiving mails in the talk section of each team.