I'm now using Fooljay's darn nifty MT-Blacklist plugin to stem the slow-rising tide of Viagra ads in my Seven Things comments. I didn't have anything like the problem that the Nielsen Hayden's were having, but one or two pieces of spam a day was quite bad enough, thank you. The plugin very nicely put together; I'm using version 1.5, which hardcodes all the rules that block suspicious comments, but Red put the more flexible 1.61 on the Hungry Tiger, and if she doesn't have any problems, I think I'll upgrade to that. Highly recommended for anyone using comments on an MT weblog (and the regexes seem like they'd be useful for anyone writing their own comment spam blocker for another system).