[stcredzero]

When I'm using the thing for reference, having only 1/10th or even 1/20th of the battery power is just fine! When I'm at my desk programming, I can probably have the thing plugged in. Even if I'm being a musician and using it as a "starter" or a fake book, I can probably have it plugged in. In that context, 4 hours of battery is usually plenty, anyhow.

Also, in this "reference" mode, the system could turn off the 2nd display until it's actually touched.

The way this flip thing would work, is that you would fade from the "cover-flow" animation to a larger, scrollable image of the text. Flicking to the side would fade you back into the cover-flow animation. It would be better if the whole display were used, but the smaller horizontal slice of a page would work too.