Microsoft Live Labs is currently developing what could be the next Google Earth-style hit - Photosynth.

Photosynth takes a large collection of photos of a place or object, analyzes them for similarities, and displays them in a reconstructed 3-Dimensional space. This means you can Walk or fly through a scene to see photos from any angle, seamlessly zoom in or out of a photograph whether it’s megapixels or gigapixels in size, and see where pictures were taken in relation to one another.

The technology works by scanning collections of photographs, which can be taken from different cameras at different times. It picks out distinctive features in each image and cross-references them against the other photographs, checking for similarities. This allows it to pinpoint a feature's 3D position and to also calculate where the position of the camera would have been when the picture was taken.

For a full explanation click here, and for a video click here. It looks very cool, and should be ready very soon.