The ellusion of debth inside: http://www.youtube.com/watch?v=ONIztGNEpYE#t=47m01s
With that.. I can Oggle at the awesome Wedding Cakes in the displays! :D
I'm hungry now.. BRB.
A few hours later.
Ohh.. i just though of another interesting use for this effect.
Reflections in Puddles: http://www.youtube.com/watch?v=iAvupgMlvKE#t=3m14s
If we can apply the ellusion of debth to the waters image reflection layer, it will look like the reflection is much farther away, when you rotate around the puddle of water.