Zmarties

Microsoft Research have released an experimental program called Group Shot that, in their words:

creates a composite image from a series of photos. The photos must be of the same scene, taken from the same point of view within a short period of time. The application uses regions that you indicate to build a composite image automatically.

Its aim therefore is to let you take a bunch of photos of the same group of people, and then to produce a composite one where the participants weren't blinking or looking away from the camera etc.

Its certainly a specialist photographic requirement, but one that many people occasionally hit.