Must-Have Extensions for Thunderbird 2.0

Operator writes "While Firefox has been in the spotlight for some time now, Thunderbird has yet to enjoy the same wide adoption or glowing praise despite being an excellent email client. It's no surprise that a popular topic has been Firefox's best (and worst) extensions while Thunderbird add-ons have gone largely unnoticed. In celebration of the recent release of Thunderbird 2.0 here are the best extensions for the program along with some honorable mentions."