Referer Realtime Black List looks to be the next needed thing if you want to have useful "referer" entries in your httpd logs.  Well, I suppose an Apache module will be needed too, perhaps a simple hash table with offending referer URLs so you can drop the connection or add a special tag to that logfile entry, etc.  I remember talking about this sort of thing a couple of years ago with Joe and we were both blown away that the spammers had not exploited referer entries.  We both thought it would only be a matter of time before they started wrecking this useful tool.  I'm surprised it has taken this long to really start picking up steam.  Look for your webserver to start handling tons of useless connections in the very near future.  It makes no difference to the spammers if their effectiveness is minimal.  And I have a feeling we'll be spending time/money to combat the issue before too long lest our servers get overloaded with "requests" for useless purposes.  Yippeeee!

Right  now I'm seeing "links" to presidential candidates and nude celeb photos.  I wonder what's on deck?