Maybe it's obvious, but Mozilla Thunderbird is not a usable alternative to Outlook 2003 . After playing with Thunderbird 1.0, it is a very well done email client app, perhaps the best Windows email client from someone other than Microsoft. But without a full-fledged PIM ![[WikiPedia]](http://www.mikeyp.com/css/external.gif)
, a stand-alone email client is nearly worthless to me, and probably most other contemporary PC users. And that's a shame.
There is some promising vapor on the Mozilla web site called Lightning . Maybe Thunderbird will be worth checking out again a year from now.
Oh, and if you think Outlook is bloated compared to Thunderbird, check out the memory usage reported by Process Explorer's "Peak Working Set":
thunderbird.exe 24840 K
OUTLOOK.EXE 25800 K
Palm.exe 16820 K
Pretty similar memory usage. However, when idle, Outlook reduces its memory footprint (Working Set) to under 8000 K, whereas Thunderbird never shrinks. And if I want to run email and PIM like I do with Outlook, I need to include the 16820 K from the Palm Desktop.
And just for kicks, Mutt appears to use 100 K. 
