Affiliate programs for browser games?

Hi all,
I was wondering if there are browser games which provide money or in-game rewards like gold,etc. for referring people to their site who would register for FREE ? I know a game providing in-game gold for bringing in referrals which in turn can be sold for real money to other players, but I am looking for something different too right now. So does anyone know some browser games offering real rewards or in-game SELLABLE rewards like gold etc for bringing in free registrations to their game?
Or does anyone has any Pay-Per-Registration(free) ideas ?

Dont know if its what you are asking for but http://www.mochimedia.com/

Wasn't exactly what I asked for, but still looks like something I could try.
Thanks a lot