This was a test of the nofollow module and walkah's filter patch. Almost works. Doesn't add rel="nofollow" to the URL linked to Anonymous users. Of course, this doesn't prevent comment spammers from attacking the site.
Because anonymous commenting is broken and I'm tired of dealing with comment spam, I've turned it off. I still maintain that the best way that I know of presently to make anonymous commenting unbroken is to use a captcha.