Each time we get a good discussion thread going, it seems the comment spam bots flood in. I usually try to erase these when I find them, but we were losing a lot of good discussion.
So I've taken action. I've implemented CAPTCHA on the comments here. That's a "Turing test" which requires you to type a random set of letters, which are displayed in a funky way.
I don't like CAPTCHA. I do piss-and-moan about it when I find it on other blogs. But I now know it's necessary, and I apologize to all for that.