There’s a restaurant in my neighborhood in SF called Luna Park that uses Twitter to send out fun promotions (http://twitter.com/lunaparksf). I went one night when they offered 50% off for anyone with a mustache. There must have been 20-30 people there with fake mustaches (some pics: http://bit.ly/3nN29).
Great story in the comments by Joe Lazarus on a post by Fred Wilson. Love the concept of Foursquare BTW.
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