We have the Comment Guard plugin on all of our blogs with the latest version. Comment Guard is our fool-proof solution to eliminate comment spam from automated bots, which constitute over 90% of comments. It protects against normal comment spam as well as trackback & pingback spams too.

This version takes care of the occasional complaints we had from people unable to submit comments. It ensures that no human comment will ever be lost. It works for Javascript enabled as well as Javascript disabled browsers.

The best part is that, with statistics disabled, it can process hundreds of thousands of spams without touching the database at all. This dramatically reduces the load on SQL server unlike other solutions like Akismet which stores every comment to the database, spam or not. Additionally Akismet, for example, makes queries across the network to identify authenticity of a comment which not only consumes your bandwidth but also slows down comment processing and takes up valuable resources which could be used to serve actual customers.

BTW: Even when statistics is enabled it simply updates a count of spam versus ham for every comment processed, one simple super-fast update in the preferences table.

So far I haven't released this plugin except for few beta customers because we didn't have the bandwidth to support before. But now we are almost ready.

We are adding some features to make it absolutely indispensable for ever blogger who ever faced spam. Look for more information about it in the comment guard blog.