A few months ago, I posted that I use Akismet in both Drupal and Wordpress. Akismet is a spam filtering service that can be used in content management systems via plug-ins and modules. The Akismet plugin ships with Wordpress 2, but some setup is required.
While visiting my Wordpress site I noticed the specific number of comment spams the Akismet filter had caught so far and made sure I took a screenshot. The image below was taken by me and I assure you that no altering of the photo was done. I'll let you be the judge whether you agree that spam through site comments represent the evil the number shown implies.
I do use Akismet to filter out the spam that is posted through comments here at CMS Report. As most of you know by now, my content mangement system of choice for this site is Drupal. The Akismet module for Drupal is now at version 1.1.2 and available at phpMiX.org (Open Source experiments).