I started using POPFile a little while ago and so far I've been very impressed. Basically its a small piece of software you install and run your POP3 connections through. It monitors all e-mails passing through and classifies them into 'buckets' (such as spam and personal mail) and you can then redirect these in your e-mail program.

It uses a clever system which assesses the probability of a message being for each bucket based on the words in it. If a message is put into the wrong bucket you access the interface and tell the software where it should have been and it will learn from its mistake. Because of this, it's not very accurate at first but can quickly become very good and assessing your e-mail.

I've been using it for a couple of weeks and so far:
87.4% of the e-mail coming in on my main account has been spam
POPFile has had 96.7% accuracy

It's not just for the Windows users either. You can either download a simple Windows install file or you can dowload the perl version which will run on any platform.

And the cost of this wonderful piece of software? It's free and it's open source:
http://popfile.sourceforge.net/

Try it. You won't be disappointed!

I might just check it, quick question though(to busy to check thier site at the moment) is it for a mail server, or the client side of things?

Client side. Just intercepts the connections from the mail program and routes them through itself.

It appears that you can run it on a server with multiple clients, though, which (I suppose means you could use it on a mail server):
https://sourceforge.net/docman/displ...rk_on_a_server

Of course its Perl and GPL, so you can do what you like with it if you know how to code it

I actually like MailScanner in combination with an anti-virus package. I use this on my servers to tage spam with {Spam} and people can filter messages based on that tag.

It also scans for virii - it cleans the messages & delivers a warning to sender and receiver.

Works like a charm!