Magic: The Gathering Online tweaks online gaming business model: "[Game publisher Wizards of the Coast] will be employing a particularly interesting new business model in conjunction with the launch of MTGO. MSRP for the title is a paltry $14.99, and there will be no monthly charges for the service (ala most MMORPGs out on the market today). WoTC is instead opting to sell virtual cards over the internet, to the tune of $3.29 for a 15 card booster pack, and $9.99 for 60-card theme decks and tournament packs. However, the most innovative new feature in this system is the players' ability to redeem their online cards for physical Magic cards."

If you know of other online services based on a razor-and-blades (or printer-and-ink) model, I'm curious to hear about them.