Good tutorial for setting up SMTP/POP3 on Debian?

Bryan Duxbury wrote:

I've been looking for a good tutorial on how to set up a mail server for
my VPS (rimuhosting) for my website (www.greekadmin.com). I've been able
to get a basic SMTP server up (postfix or exim) that can successfully
send emails from my Rails apps.

The problem I'm running into now is that I'd like to set up some email
addresses for me and my partner to check and send email via standard
mail clients. I can't seem to find a good tutorial that describes in
exquisite detail what I need to do to get outgoing email from any
address if it originates on the server, but also allow authenticated
users to send email from off-server.

If anyone could point me in the right direction, I'd really appreciate
it.
  

Ezra's "The Perfect Rails/Debian/Lighttpd Stack..." covers setting up SMTP (Postfix) and POP3 (QPopper):

http://brainspl.at/rails_stack.html