A while back, Microsoft Research created a product called AutoCollage. It’s really quite impressive how well it works. The software (as the name plainly indicates) is used to automatically create a photo collage from a set of input photos. It began as a research project, but at some point they decided it would make sense to release it as a product. They’re onto something here. It’s the easiest to use photo collage software I’ve ever used, and the results are very good, even when run in fully-automatic mode. If you spend a couple minutes to provide a couple extra hints, the results are excellent. It’s definitely worth downloading the trial version to see what it can do.
If you use Windows Live Photo Gallery, it’s even easier to select and create collages using AutoCollage, due to the integration into WLPG. You can select you photos based on tags, or any other criteria available to you in WLPG.
Here are a couple samples of what it can do:
