1.) zen.spamhaus.org – http://www.spamhaus.org/zen/
2.) rhsbl.ahbl.org – http://www.ahbl.org/documents/rhsbl
3.) truncate.gbudb.net – http://www.gbudb.com/truncate/
4.) b.barracudacentral.org – http://www.barracudacentral.org/account/register
5.) bl.blocklist.de – http://www.blocklist.de/en/api.html#dns
6.) dnsbl.dronebl.org – http://dronebl.org/docs/howtouse
7.) new.spam.dnsbl.sorbs.net – http://new.spam.dnsbl.sorbs.net/
8.) nomail.rhsbl.sorbs.net – http://nomail.rhsbl.sorbs.net/
9.) zombie.dnsbl.sorbs.net – http://zombie.dnsbl.sorbs.net
10.) srnblack.surgate.net – http://www.srntools.com/
11.) dnsbl-1.uceprotect.net – http://www.uceprotect.net/en/index.php?m=6&s=10
12.) all.s5h.net – http://www.usenix.org.uk/content/rbl.html
13.) ubl.unsubscore.com – http://blacklist.lashback.com/
Source:
http://www.webhostingtalk.com/showthread.php?t=1317685