You've got to be really careful when doing something like this. Basing the decision to display porn to users based on the value of the referrer (or any technica

You've got to be really careful when doing something like this. Basing the decision to display porn to users based on the value of the referrer (or any technical factor for that matter) is asking for trouble. Valid visitors' browsers should send your site as the referrer, but what if your check fails and a legitimate users is shown porn instead? What if you introduce a bug that causes many, or all, of your users to see porn instead of the intended content? Serving porn from a business oriented domain is never an option, IMO. It sucks when someone rips off your content, but you have to carefully evaluate the real impact it has on your business, not just the emotional impact that it has on your sense of ownership.