Several weeks ago, Dries Buytaert (Drupal) and Benjamin Schrauwen presented their new start-up: Mollom. Their new company provides anti-spam services. Much like Akismet. (Benefits and Technical Details)
They support a plugin for Drupal and recently released API documentation to enable third parties to develop their own apps on their service.
In close cooperation with Dries and Benjamin, I developed a plugin that brings the power of Mollom to WordPress. At this point, I need volunteers who are willing to try out the plugin and send me feedback.
So, if you are interested, want to join in and give it a go: please contact me at matthias at netsensei dot nl.