The Bouncer -- Prevent other sites from linking to a page on your site.
If you have a page on your site (such as a music archive) that you don't want other sites to directly link to, but you want them to link to your main page, The Bouncer will make sure that no longer happens. It will redirect any user that isn't coming from your site, to the URL of your choice.
http://www.smarterscripts.com/bouncer/