While we are still some years away from the screens of tomorrow that I imagine (low powered lasers in your glasses that would paint virtual screens directly on to your retina), I think this is a big step forward in the input problem. The soft-key interface of the iPhone proves that people can get by just fine without physical buttons. Personally it took a long while to get used to, but in time I’ve discovered that I can type far more rapidly and accurately than I ever did on my Palm Treo with its Blackberry style keyboard.

So to take this concept a step furthere, why waste valuable screen real estate with keyboards, buttons and other interface elements? If you can turn the body itself into an interface device, perhaps by making our fingertips into sensors, than any surface could be used for soft-keys.