Very interesting read at
http://www.zimbra.com/pdf/Zimbra%20Fixing%20Email%20Whitepaper.pdf
Open source email/calendaring. Time to see if I can make this work on BSD… It works on OSX, perhaps there is hope. I would LOVE to see a Windows port too… Oh and the great part, it isn’t GNU….
http://www.zimbra.com/community/documentation.html
Also, a very cool demo at
http://www.zimbra.com/products/hosted_demo.php
You don’t have to register, you can skip it.
Screen shot of demo