A business model/process is described for conducting business transactions over the Internet, allowing buyers to reduce the price of the selected product/service based on the buyer's performance during a collateral activity. Sellers offer the product/service within a specified price range, and buyers accept the offer, in exchange for the opportunity to close the transaction at the lowest price offered by achieving a high score during the collateral activity. The ultimate price is within the agreed upon range, but is determined based upon the buyer's performance during the collateral activity. The activity may be a video game, electronic board game, sports bet, card game, or any other activity, and may be performed against the seller, a pre-programmed software opponent, a computer opponent, another buyer competing for the same or a different product, a player participating as a player only and not as a buyer, or anyone or anything else.