Any recommendations for a Linux/BSD based community Spambox?

I'm looking for an integrated distribution/VM appliance to do virus and SPAM filtering, much in the way that spamtitan does it.  Having a GUI for users would be a huge plus.

So far, I only found proprietary solutions, so if anyone knows a community project that does the same, please recommend it to me!

Thanks

PS.  Yes, I know mailscanner and amavis, been running them for years :-)