ARGH!!! I may have to turn the comment function off on most of my posts - as spammers keep adding comments of their own. Sometimes it's an innocuous remark, sometimes it's verbal garbage, but it links to their sites. I try to clean the stuff out and ban IP addresses as I go along, but it is getting bad.
Mark Pilgrim has some good words on the philosophy of spam fighting.
Meanwhile. Watch how you click on any address or email links in my comments. I'm going to turn off the html in comments, as well, for now. Sorry.