Pico projector used to leverage a phone into a collaborative system
Researchers from the University of Duisburg-Essen in Germany developed a new system that allows for synchronous collaboration during phone calls. The idea that if you talk on the phone, you cannot use the phone's display, and in any case the display is usually too slow. Using a pico projector you can project an image on your desk while speaking, and use that as an interactive collaboration system. Check this video to see a prototype system which shows possible UI for sharing documents, maps, calendars, etc:
While the prototype looks a bit clumsy, this can be achieved with a projector phone that will allow projecting in the right direction.