Reverse Dos spam trackback protector. You can chuck all the offending domain names and words into
its configuration file and stop them to create referrer records on your
database. A quick analysis on my database showed 600+ spam referrers. I copied
them to an Excel sheet and created these filters. It boiled down to 274
unique domain names including the ones on RDos config file.
Now My blog is free off spam trackbacks.