Here’s my “Top 3 WordPress Anti-Spam Plugins” for Q4 2012:
- The Stop Spammer Registrations Plugin checks against Spam Databases to to prevent spammers from registering or making comments.
- Simple question that blocks most spambots (and paid robots) by making them answer a common sense question
It’s what I use on my blog in conjunction with CloudFlare and my personal customizations. Although, I’ve replaced WP No-Bot Question with my own variant called No-Spam IP Geolocation, but it only works if the domain is behind the CloudFlare service and if IP Geolocation is enabled in the CloudFlare-settings of that particular domain.
In any case, when these three plugins are used concurrently I have had no spam going through to my blog at all. A tip for using WP No-Bot Question is that you should set a question that is difficult and not widely used, thus lessening the chances that the automated spambots have the answer stored in their database.
Short and simple.