I've made some big progress getting the email working.
Brian, I was looking at the How-To that B. Densmore pointed me to at www.amason.net.
So far, the following working: 1) Sending and receiving local and remote mail from mutt or squirrelmail. 2) Mail is getting to ~/Maildir so IMAP stuff works. I can setup the IMAP connection via thunderbird, and pull mail from there. 3) Fetchmail is pulling mail from a pop3 account, and dumping it into my local account.
Here is what's not working yet. 1) Fetchmail only runs when I tell it to (either with commandline or the webmin interface). I am supposing that cron could handle this for me, but want to make sure there is no built-in fetchmail periodic checking feature that I'm missing. 2) I _really_ want to find out if there is way I can get fetchmail (or something else?) to put mail it gets from the pop accounts into IMAP folder based on which account it pulls from. 3) I still need to get exim to send via my ISP's smtp server for those domains that block dynamic hosts. I was reading that you can set it up to only use the smarthost for some hosts, and not all. I'm not sure if it would be better to selectively use the smarthost, or to use it for all mail.
So...huge improvements! It's being really fun to mess around with this stuff too.
I'd love any comments on the remaining items, if anyone has been through this type of thing.
Matt