Engineers at Yelp have put together an Arduino and iPad controlled Keg-o-rator.  By swiping their RFID they can track how much a person is drinking, collect statistics about how others enjoyed the beer (by rating it), and maintain a leader-board of the office.  Everything used in the project is based on off-the-self components.  My guess is that they are communicating between the iPad and Arduino over the iPod Dock’s i2c interface.  It looks like they…