So for the last month or so I've been getting hammered with spam in my journal comments. 99% of it is for some Propecia reseller website. Initially, it was all coming from a small number of IP addresses so I used MT's built-in IP blocking capability and all was well, but then it started coming from a different IP every time and it was taking a lot of time for me every day to remove all the comments.

So with Jason and Mark's help, I found a great MT plugin called MT-blacklist that borks any attempt to post a comment to my journal that includes a link to a URL that is on a very large blacklist. I tested it against some of the Propecia spam comments and it nuked them immediately. Now I'm golden.