Automatic Photo Pop-up by CMU group

Stumbled upon this press release through Engadget.

Carnegie Mellon Researchers Teach Computers To Perceive Three Dimensions in 2-D Images

They even have Matlab code available on their Automatic Photo Pop-up page. Sure to try it out sometimes.

The paper:
D. Hoiem, A.A. Efros, and M. Hebert, "Automatic Photo Pop-up", ACM SIGGRAPH 2005.