Check out this neat new project at anonwhois.org: It's domain data, published in a format similar to a URI DNSBL or RHSBL (right-hand side BL). Meaning, in short, it's a DNS-based list that you can check domains against. What does it tell you? Whether or not a domain is registered anonymously; that is to say, whether or not a domain is registered behind a "privacy protect"-like service. Like many other spam fighters, I've long considered it a bad idea to hide ownership of your domain in this manner. And now, if you, like me, think it's a bad idea, you could use the ANONWHOIS data to help score or otherwise identify messages that come from such domains or use such domains in images or links.