Imagine this: You're strolling virtually through your favorite Google Street View destination, when suddenly you notice an animated ad on one of the billboards beside the street. "Buy product X," it beckons you, replacing the obsolete ad that was originally on the billboard when the Google Street View car took the picture.
This might very well turn into a reality. Google has been granted a patent named "Claiming Real Estate in Panoramic or 3D Mapping Environments for Advertising," detailing "techniques for identifying groups of features in an online geographic view of a real property and replacing and/or augmenting the groups of features with advertisement."
The idea is ingenious, really. Most of those obsolete ads on billboards serve very little purpose in the virtual world of Street View, but if one could replace them with up-to-date advertisements, they could be another source of income for the giant from Mountain View.