Tackling Comment Spam is a page of information about comment spam, and plugins for fighting it.
* Kitten’s Spaminator, which combines tarpitting (making multiple comments from the same source take longer and longer to post, in order to slow down bots), and a “three strikes” method, where the spammers IP is blocked after three spams.
- Kittens Spam Words, which gives you a “delete as spam” option, which automatically adds the email address, URL, and IP address to your Spam Words File.
- Laughing Lizard’s Comment Preview, just requires the user to click an extra button to post. Spambots aren’t smart enough to do that.
Not listed, but also VERY useful:
* URI Blocklist, which checks the URLs in your comments to see if they advertise known spammer sites.