E-paper & ultrathin displays are going to be the source of all kinds of amazing applications. I'm looking forward to the day when I can design motion graphics for e-packaging & other surfaces that will use this emerging technology.
I saw this awesome concept called Nokia Morph on a couple different websites. It is a glimpse into the exciting & innovative creations that are just around the corner. Everything is cool about this - the styling of it, the translucent green, the interface visualizations... it's like the iPhone of the future.
There is really no reason why this device can't exist right now. It's only the misuse and waste of our collective resources and potential that prevents the realization of such inventions.