The problem for me is about how we input something in the machine. iPad, Kindle, etc. are wonderful for consuming content, and this can probably be done efficie

The problem for me is about how we input something in the machine. iPad, Kindle, etc. are wonderful for consuming content, and this can probably be done efficiently enough with touchscreen interfaces. But producing content is one important part of the deal (specially for guys like Tufte), and in this activity the physical grain of the interface become prominent. In my dream, I would have a phone-like thing, small enough to fit in my pocket. I would be able to put it on a flat surface and two laser rays would draw a rectangle were I would be able to draw or write. What I draw would be projected on the surface by the laser in real-time, so I'd have the feedback that is missing on electronic draw-pads. With this we would go back to hand-writing for most of us, and it would be possible to have a keyboard drawn on the surface and use fingers. The haptic feedback is the hard part, but I think laser can't "touch" you so I don't see how to do it.