If you've ever experimented with the maps by Google, you know at the click of a button you can see a satellite view of what your looking at.
Target stores, in a genius move, has realized the popularity of this technology and have painted some of their rooftops.
Here's an actual satellite pic of a Target store near Chicago.
I thought it was a joke when I first heard of it, but no.
Edit: Oops. The rooftop art was originally done because the Target was near an airport.