I think that paypal charges a low percentage if the money comes from within a paypal account.. and a high percentage if someone is paying with a credit card through paypal. Since Renderosity has an alternate way to process credit cards, they only need to use paypal for payments that originate from the account. I just looked at their site.. and if Renderosity became "Pay Pal Preferred" (which I think only involves signing up to get interest on their money.. an added bonus).. then their fee is only .7% plus 30 cents per transaction... with NO fee for international transactions.