This levitating projector may just be a concept, but most of the science is fairly sound.
While projectors traditionally use lenses to offset the throw of the image (pretty effectively, I might add), the floating ball (suspended from an electromagnetic base) can rise or fall in space to make projection even more flexible. Plus, the projector is not just a projector but a series of microprojectors, allowing users to display multiple images to and from multiple angles. So little Billy can watch the latest Power Rangers on one wall while you pretend to watch CNN on another.
Of course, by the time microprojectors are good enough for home theatre use, we'll probably all have HD imaging paints anyway and just cover our walls with electronic wallpaper. (A guy can dream, can't he?) [Yanko Design]