What Tom Coates describes here also happened to me when I upgraded to Movable Type 3.14 late in 2004.
When they try and login, the server basically falls over completely. A forced restart, and I hold my breath a little. When it comes back, they dig into the logs and it becomes immediately obvious to them what’s going on. Hundreds – thousands – of requests every minute for a file called mt-comments.cgi – the part of Movable Type that deals with incoming comments to my weblog. My entire site has been quite directly, and clearly spammed to death.
Every once in a while I consider bringing back comments on Waffle, possibly after upgrading to a newer version of Movable Type. Then I think "Naaah." I didn’t get too many anyway, and restoring the feature would require quite a lot of work up-front and also bring along with it an ongoing responsibility to maintain it – keeping it functional and spam-free. Life’s too short.
WillowCMS, on which the comic’s archive runs, has comments, and seems to be holding up well under the onslaught of spamming attempts. But should it buckle under, I don’t think I would wait very long to cut my losses and switch off comments.