I’ve detailed some of the struggles I had for a bit with FLOODS of comment spam. Details of the issue and a fix which has been rock solid for WordPress can be found in the following posts (reverse chronological order): Update on comment spam storms, trackback spam countermeasures such as akismet and trackback validation, another trackback storm, botnets spreading trackback spam?, Initial trackback storm. To sum up though, I’ve found 2 plugins to make for a rock solid combination here in wordpress. Akismet (which caught 99% or so of trackback spam) and The trackback validator plugin which caught everything else. (99% sounds good, but when you’re getting thousands of attempts a day?)