Exim Notes
Exim is Debian's standard MTA (Mail Transport Agent). I don't know that much about it, but I seem to be able to coax it into doing what I need most of the time. However, especially since Exim 3 is getting kind of old, it's sometimes hard to find examples. I'm just using this page as a collecting point for Exim things that took effort to figure out.
You might also want to look at the MailingListNotes page for notes on making Exim 3 work with EoC and MHonArc.