trinorthlighting - 10:12 pm on Apr 15, 2010 (gmt 0)

If you want to really put a dent in spam emails and you only do business in North America you can block RIPE, APNIC and AFRINIC networks from your servers you will reduce 50% of your email spam. Add to that, your users will be happier because your server will be faster because you will block over 1/2 of the malicious bots eating up bandwidth on your server from those IP ranges.