It occurred to me this morning that it would possible to build a camera that would refuse to take certain pictures. Using image recognition, stored patterns and images, central databases, and location and orientation sensors, we might find ourselves no longer be able to photograph famous landmarks, works of art, celebrities, or any scene whose composition was deemed too similar to a registered image.
Maybe the objects of interest would get blurred out unless you paid a licensing fee, which you could do on the spot using your camera (which is probably also a phone, browser, etc).
Augmented reality systems will quickly become a delivery platform for advertisements. Will over-zealous copyright enforcement be far behind?