Blacklists do help in the fight against spam

I was feed up about all the spam we were getting.  I have been getting 150+ spam messages per day.  That was just not acceptable.  As a result, over the weekend, we started using the Realtime BlackLists on our mail server.  We have implemented the following urls:

• sbl.spamhaus.org
• bl.spamcop.net
• dnsbl.njabl.org
• cn-kr.blackholes.us
• relays.ordb.org
• list.dsbl.org
• unconfirmed.dsbl.org
• multihop.dsbl.org

After implementing these RBLs, my spam volume dropped down to about one spam message everyone 1-2 hours.  The RBLs don't seem to help on the spam that comes from the botnets.  I got 10 spam messages all about OEM software in a ten minute span this morning, most likely someone with an infected PC turned their PC on this morning.

If you have any additional RBLs that you highly suggest or some suggestions on fighting the botnet spam, please send me a suggestion in the comments of this post.