Seems like the spammers have found the web equivalent of an smtp open relay. For example: [http://wiki.cs.uiuc.edu/VisualWorks/DOWNLOAD/sb/index.htm sitz bath] [http://www.buddy4u.com/view/?u=monophonic+ringtone monophonic ringtone] [http://www.buddyprofile.com/viewprofile.php?username=nextelringtone nextel ringtone] These are links to legitimate sites that perform poor input validation... The spammers have managed to convert the pages into http redirects. Because of how the various search engines work a link to a redirect page is just as good as a link to the redirect target. Since the spammers can make an infinite number of unique URLs at these sites, blocking the exact URL is pointless. So right now our only choices are to block legitimate sites because their poor hygiene allows them to be used as a spam-bouncer, or allow ourselves to be spammed with these sites and contribute to the declining usefulness of the internet. Things like this make nofollow more attractive all the time. Has there ever been any discussion on perhaps allowing a white-list for non-spam sites that we won't no-follow? This would be useful for wikis who don't want to kill all their externals with no-follow.