Viking from robban
http://www.robtex.com/viking.html
HTTP, mail, ftp, socks, dns, and on and on. It does it all.
I have been running it as a hobby server for 9 years now with no probs.
Little tiny footprint, it's written old style, entire thing fits into a 844k file.
I run most of my mail off it, a bunch of dns and several sites.