NerdKey

Created to work alongside the NerdTools Bad Bots Spam Reporter & Spam Defender plugins, this plugin will read all comments posted to detect common spam elements and proceed to mark the comment as “spam” automatically if a match is found.
More information can be found at http://www.nerdtools.co.uk/badbots/

NerdTools Comment Filter

This plugin will read all comments posted to detect common spam elements and proceed to mark the comment as "spam" automatically if a match  …

Powered by NerdTools.co.uk, this plugin will automatically and anonymously report the authors IP address for any comment that is classed as spam to the NerdTools Bad Bots Intrusion & Spam Detection database.
The Bad Bots database keeps track of hundreds of thousands of bots that try and exploit and spam servers and websites world wide which is then used in applications such as NerdTools Bad Bot Spam Defender which checks every comment authors IP address against the database to detect and prevent known offenders from causing further spam.
This plugin is simple to use, follow the installation instructions and you will be contributing in no time.
More information along with stats and the NerdTools Bad Bots Spam Defender plugin can be found at http://www.nerdtools.co.uk/badbots/.

NerdTools Bad Bots Spam Reporter

Automatically report spam comments to the NerdTools Bad Bots database. The authors IP address is sent anonymously to help understand and fight spam.

NerdTools Comment Filter vs NerdTools Bad Bots Spam Reporter