Although these days I find myself just using gmail, I've used Netscape Mail / Tbird iterations since college and have always preferred them over the competition.
Whenever I finally decide Google has become too intrusive and I switch to another email provider, I'll go back to Tbird as a local mail prg (I know I can use Tbird with Google, but am too lazy).
I actually still use Tbird as my email archiver. When I left work, I downloaded copies of all my emails to a local Tbird account on my Linux VM. Super easy to just start the local account and have all the work folders pop up in an easy to peruse way.
