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In China there's a popular consumer practice called tuangou or "team-buying," in which a large group of like-minded shoppers meet online and organize a trip to a local store. On that decided-upon day, they all show up in a huge pack and offer to buy, say, 75 digitial cameras from the store owner, but only if he'll agree to a 25 percent discount. If the owner doesn't agree to the deal, they all walk out. Instead of spending all their time developing better ways for Facebook users to poke each other or play board games online, why don't widgetmakers use the "social graph" to determine which users might have like-minded shopping interests, band them together and send them as a pack to amenable online and offline vendors? People have tried this before, but they didn't have acess to all of Facebook's data. I'm sure nobody would mind such an actually useful service taking a PayPal-esque cut off the top, Mr. Levchin.