The pilot program offered through OCLC provides WorldCat users the opportunity to recoup a portion of their fees through book purchases. The program was described to this wiki in an email from Chuck Costakos of OCLC:

"Thanks for the note. It looks good on your page!

I’ll explain briefly how this all works and you can tell me if you have more questions. First of all, we consider this still a pilot activity. It seems to be working fine with no apparent problems, and Open WorldCat users do find it useful sometimes to buy items they find in WorldCat, for a variety of reasons, I’m sure. We will probably continue it and expand it by offering more choices of sellers, including some that specialize in certain types of items (musical scores or rare books, for example) and who serve different parts of the world.

We actually have two programs. One is with Baker & Taylor. In that case, the users can designate a library they want to support before they actually buy something. B&T keeps track of that choice and reports it to us. We get referral fees from B&T for each sale, and we provide a fourth of that amount to the libraries identified. It comes in the form of a deduction from their OCLC invoices. If users do not choose a library, the referral fees go to the enhancement of Open WorldCat. Libraries can opt out of this revenue-sharing program if they wish. There has been so little buying in this program that the amounts of money are negligible.

The second program is with Amazon. We do not ask these buyers to choose a library to support because Amazon does not (cannot, actually) keep track of those choices and report them back to us. Therefore, we have no accurate way to determine which library should share in the referral fees. Since the B&T amounts were so small, we just introduced the Amazon links without any revenue sharing. We use the referral fees to support ongoing enhancements to Open WorldCat. If this proves to generate a substantial amount of money, we will look at whether and how we divide that money with the users’ libraries."

More information is provided at OCLC.