Sam Ruby has some stuff on comment spam. I've written before about weblog comment spam and why I don't think it will be a long term problem. Sam's comment throttling is an example of how we have so many more approaches to deal with weblog comment spam than we do with e-mail, and I didn't seriously factor approaches like this into what I wrote before.
So I'll reiterate, I don't think weblog comment spam will be much of a long-term problem. But, I really do have to implement comment throttling on my web site before I get hit with a massive spammer like Sam did.
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