The effect of staring through to a point to make a picture 3D has been used quiet a bit for things like the '3d magic eye' post cards etc for years now. I can't remember, but the effect of depth has a special scientific name. Does anyone remember the fad for all those 'magic 3d' and 'magic eye' books and pictures they had in news papers and mags etc? I had a few books - its quiet a skill to get them to work but basically a picture that looks like a mess suddenly becomes 3d and the picture of a dolphin, city scape or whatever jumps out at you when you manage to force your eye to focus on a point thats actually behing the page.
I will try and find a few links. You can also get software that produced the images for you.