I agree with you that the composer-style arm flailing is not great (even if intuitive to non-techies), but I do consider smaller, closer-proximity gestures a pe

I agree with you that the composer-style arm flailing is not great (even if intuitive to non-techies), but I do consider smaller, closer-proximity gestures a perfectly viable direction of research. > I'm not sure how learning a set of rather specific gestures is less complicated to a novice user than hitting the right arrow key or the spacebar a bunch of times (or clicking on a button labeled "next photo"). They are just not as good with traditional computer input methods, negating the advantage that you or I would gain there. The point about 3D is very good, and something that can be workable even with 2D displays (in a "3D" environment, like your average FPS). Rotating, pulling things from "behind" something else etc. For certain categories of use, it is probably better than voice commands - another natural UI for humans - in the same way some of us still prefer the CLI over a GUI. The current technology obviously is not quite there, but it is already possible to implement a virtual keyboard by observing finger movements. Combine that with gestures performed above the virtual surface, and you might have something.