WP-DenyHost Wordpress Plugin - Rating, Reviews, Demo & Download
Plugin Description
Based on a users IP address, WP-DenyHost will block a spammer if he already has been tagged as a spammer. Use it together with the Akismet plugin. Akismet tags the spammer, and WP-DenyHost prevents him from accessing you site.
If you have a CloudFlare account, the plugin can add spamers to CloudFlare Block list