Over the past year I'd noticed that comment and trackback spammers had been hitting the same dozen or so pages of my blog multiple times daily. (It is probably the same person/group who took a snapshot of the articles on my front page at that time and just reuses those URLs for all of their different domains). Last I calculated, about 50% of my overall website traffic is due to spammers. This constant barrage of hits skews my AWStats statistics and, more importantly, skews the results on my Favorites page. So I took a little time to work on this problem.
FWIW I'm also starting to see a lot of spam coming from "blogs" being setup on BlogSpot that are a single page all of whose links point to the real site. Some of these bogus blogs use the BlogSpot temmplate which contains a flag used to alert BlogSpot admins to content in violation of their Terms of Service. This allows anyone to report the bogus blog by just clicking on the flag. Other "blogs" just use their own HTML and BlogSpot support would have to be sent an email with the offending site's URL.
So anyway, I've taken the following steps:
Another couple hours wasted messing around against spammers.
I've previously written how I've been using comment content blacklisting to reject comment, trackback, and referer (sic) spam. My current blacklist file has over 40 regular expressions containing over 250 words and patterns. I update it whenever a spam comment slips through. So that is an ongoing almost daily effort. I might just have to go to the trouble of getting a CAPTCHA plugin to work.