Hate to bring up an old thread but it's kind of on a topic I am familiar with. I write a guestbook script and one of the first things I did to help fight spam was add the rel="nofollow" attribute to any links posted. This way any links posted are not followed by the major search engines. Of course I have other anti spam methods in place such as captcha and the ability to moderate posts by email but the amount of people who think guestbook spamming is legitimate method of advertising is ridiculous and yet they don't think it is spam.

Muppets.

__________________
Carbonize