I have to tell you, I find it funny if nothing else to edit a comment entirely to remove a link to a spam site, and change the name if it is keywords, then approve the comment. I just think in my head about how mad the spammer is that he didn’t succeed in posting his spam. I only do that if he leaves a comment worth posting (put some thought into his spam comment). I did recently require free accounts to post comments though due to a massive spam issue on a post about not spamming. It’s just easier to manage.