Rarely do we see any prototype products that emerge from Apple.  This lucky member of the MacRumors forum "Brett33", purchased a MacBook Air "as is" from Ebay for $730 and once recieved, he had realized he had something very special.  The MacBook Air he recieved turned out to have a black aluminum bottom and was lacking the words "MacBook Air" from the screen bezel.  The MacBook also came supplied with the interim build Mac OS X 10.5 (8R4016).  Upon the new owners investigation, he found that the serial number was for May 2007, a full 6-months prior to the the release of the MacBook Air.  Although not often seen, Apple prototypes have been seen in the wild.

 

[via MacRumors]