Mozilla has released Thunderbird 3. The best email client ever?
I've used Thunderbird for several years because I prefer its built in color tagging of messages. Recently, I installed the beta which preceded this latest official release. What makes this bird different? The interface has been modernized and it can be re-skinned if you are the type that likes to tech-ccesorize. There are also several usability enhancements like viewing multiple messages at once. Here are a few more standout features.
I'm a heavy tabs user in my browsers and I love it as much in my email client.
Thunderbird 3 has by far the most impressive search and filtering I have seen.
There are a number of extensions that expand Thunderbird's functionality. Google Calendar integration interest you?
The biggest plus is that it is free. Thunderbird is worth a look and can be downloaded here.