Here’s an interesting little project that, while it’s unlikely to grow into a major product, nevertheless demonstrates the potential of alternative interfaces. Bruno Zamborlin’s Mogees (an abbreviation of “mosaicing gestural surface”) takes input from a contact microphone and analyzes it to determine the placement and direction of gestures on any surface through which vibrations can be detected.
I wrote a while back about how the “finger on a glass touchscreen” wasn’t the be-all and end-all of user interaction. The stylus, for example, has much life left in it. And interfaces we haven’t even thought of will emerge as well. Why not a puck that turns your table into a touchable surface?