1 Registration, at least you know who the trolls are.

2 Agree. If you want to post on the site then you have to register. Surely there is a way to block spammers if you have to register?? Karol over at Alarming News had a similar thing if i recall and registration was floated as an option.

3 I've found that blocking comments with multiple dashes keeps out 99% of the spam. Try adding "-.*-.*-" to your Mt-Blacklist setup. Of course, you'll have to install MT-Blacklist if you haven't already.

4 MT-Blacklist is the way to go. When my site was on Movable Type, it was the best tool to keeping spammers out. (Great site, as always, Michael.) If you need any assistance with installing/configuring MT-Blacklist, let me know. Jay Allen developed it and has it available here: http://www.jayallen.org/projects/mt-blacklist/

5 We should hunt spammers down and shoot them. I got over a hundred comment spam entries one day. My total real hits per day is only a hundred and twenty or so. Fortunately, they don't hit WordPress quite as often as MT.

6 I've installed some new filtering software, and just in time too. (Well, sooner would have been better, but I had to write it first.) In the past hour it's blocked a couple of hundred comments just for your blog. It looks like it's some sort of distributed tool specifically designed to crap on blogs. The idea, most likely, is to clog up spam filters to the point that they don't work any more. Either that or just to make a mess and annoy people. There's a group - I won't bother naming them - whose aim is to destroy Movable Type blogs. Yes, specifically MT blogs. And I thought I had no life...