I’ve found an interesting page:
This project when launched will allow you to create a 3D model from a plain image, the demos are astounding.
This idea are fully explained in this tutorial: http://www.cs.unc.edu/~marc/tutorial/
Also I’ve seen Microsoft is also launching an app: Photosynth (http://labs.live.com/photosynth/default.html)
Update:Virtual tourism as called by Microsoft seems to be an oustanding and a future development which will change our ways to know places through photos: http://research.microsoft.com/IVM/PhotoTours/