One of the setbacks of running a very popular website (imagepile.net) is the amount of spam that can be thrown your way (not to mention random DDoS attacks and the like). There isn’t much you can do about attacks other than do the best you can to mitigate them, on the other hand spam is super easy to block. If you are the proud owner of a large domain and the lucky recipient of hundreds of spam emails, check out qmailrocks.org , they’ve got a great simple tutorial to setup your very own Qmail server with Anti-Virus and Spam filtering thanks to ClamAV and Spam Assassin. They provide a great step by step tutorial for all popular *nix distro’s.
Oh and did I mention it’s free? suck on that M$ Exchange