I use this for an SMTP server http://www.postcastserver.com/

Linux/BSD running sendmail or postfix work great.

If the box isn't going to see much action, you could install that on a very low-end box, and be in pretty good shape.

Hmm... now why did I just know that was coming? :mrgreen:

i use merak mail server, Its cheap and reliable.

If the computer is connected to the internet perminantly that hosts the mail server, make sure you secure the relap server (this is try for any mail server) as you will become an open relay very quickly if you dont.

the easiest way to do this (assuming you do not need to be able to send messages from outside your network, is to disable port 25 (SMTP port) from being accessed from outside your network. Otherwise use the built in security features.

jack