I like the shadow reaching technique because it is using a phenomenon that people already familiar with. Therefore, people can learn it quickly. Would the size of a virtual shadow be a good feedback to the user when using our proximity designs such as Till's Media Player? I think it is a good way of telling the user that the display is distance sensitive.
I don't quite agree with the fact that people avoid intruding other people's shadows. I personally feel that the shadow is partially restricted by the environment, so it shouldn't have a social impact on its position. However, if indeed such feeling exist, would Hall's proximity theory apply to shadow as well?
