It looks like Amazon has a new competitor coming, in what looks like a Costco like model on the web, with some kind of an online membership shopping program. For details, see this Business Week article: Amazon Bought This Man's Company. Now He's Coming for Them.
They're giving away 100,000 free 6 month+ memberships if you get enough friends to sign up. Top person actually gets 100,000 in stock options. Sign up now and get started getting friends to sign up.
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