I popped in the WordPress forums this morning, and skimmed through a thread where someone was asking how to get rid of trackback spam. Since Tom Raftery says there might be a wave coming, I thought I better get some reinforcements.
Other than that, I’m not using any other plugins like Kitten’s Spaminator (source) or Spam Karma. In here, I’m still using built-in detection methods and holding up well without additional plugins. (Does the Auto Moderate Comments count? 😛 )