Industry of the Ordinary provide an associate with a locked box which is then buried in the desert. Coordinates are recorded in a sealed envelope which is made available for purchase here.
UPDATE MAY 2012: Exact coordinates of this box have been lost. It can be found by using a metal detector and scanning the west shoulder of California Highway 93 between Wendover and Ibapah Road in a 200 foot radius. Alternatively, you can engage with the updated project here.