> Not sure about input; gesturing to yourself is going to look even crazier than talking to yourself.

In the early seventies I used to carry my Philips portable cassette player and headphones everywhere, people thought I was crazy until Akio Morita had the same idea and got Sony to create the Walkman. Now people wear headphones in the street and hardly anyone thinks about it at all.

My point is that what you think is crazy now might well be normal in ten years time, or perhaps even tomorrow.