This is kinda hard to explain, but I've seen it several places before. I'm looking for a special way that two photographs are printed — they're printed so you from each angle can see just one of the two photos. It's printed on a load on triangles so if you're looking from 90 degrees you wouldn't really see anything, but from approximately 60 degrees and 120 degrees, you can see the two photos.
see photo two see photo one
I'm looking for the name of this printing style. I hope it's explained so you can understand it.