Pictcha is a very unique & secure CAPTCHA.
Correct comment's ip address with X-Forwarded-For http header if you are behind a proxy or load balancer. There is no setting. It should start working
Highlights blacklisted words in comments.
Check the comment for a set maximum length and disapprove it if it's too long.
CommentSafe is a very simple plugin which removes (X)HTML tags you specify from your comments.
Comment Numerical Captcha Plugins
Extremely basic, no-configuration registration spam bot trap
A script which protects the comment form from spam. Does four ways of protection.
"WP-NoSpamUser" is all about blocking potential spammers from registering on your blog.
This wordpress plug-in will put a link to each posts and pages to report that particluar post or page.
Close comments, pingbacks and trackbacks on your posts automatically at intervals set by you
Checks via Google Search if the comment being left is a common spam comment.
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