The New York Times writes:
In their new incarnation, cellphones become a sort of digital remote control, as one CBS executive put it. With a wave, the phone can read encoded information on everyday objects and translate that into videos, pictures or text files on its screen.
The most promising way to link cellphones with physical objects is a new generation of bar codes: square-shaped mosaics of black and white boxes that can hold much more information than traditional bar codes. The cameras on cellphones scan the codes, and then the codes are translated into videos, music or text on the phone screens.