Weekly reports of DNS blacklists lookups of IP addresses (and reverse DNS lookups) that made SMTP connections to the San Diego Supercomputer Center on that week. Useful for getting a grasp of the size of the various blacklists. Maintained by Jeff Makey.

Blacklist that includes dialup equivalent ip addresses, individual spam sources, netblocks that refuse to remove spammers, bulk mailers that don't require confirmed opt-in, output servers from multi-stage open relay chains and single stage open relays...

RHS-style lists of domains which have sent spam to MailPolice customers. Currently divided into two lists, bulk senders - domains associated with bulk mail - and pornography - domains associated with sending and hosting pornographic content.

Lists IP blocks of China and Korea for those who want to avoid asian spam.

As a public service, McFadden Associates maintains a free DNSBL blacklist. Anyone sending SPAM into their mail filters is automatically added for a period of thirty days.

List of domains that have been advertised via spam, with name server, registration date, registrant. This list is updated daily.

Attempt to generate a free realtime black list of spammer IP numbers.

A permanent blocklist of spam supporting web hosts and ISPs.

Provides reports on whether there is recent spam activity within each IP block, especially spamvertised web site addresses. Check if you are sharing your address block with spammers.

A manually updated and verified online database of spammers. Provides email address and domain blocklist.