Interesting questions one and all. Let me raise one of my own.
Have any of you looked into using an e-book, such as the Rocket e-book?
(http://www.rocketbook.com/)
it would seem to answer a lot (but not all) of the questions. It's
portable, it can work anywhere, it's cheaper than a PC, and it can be
downloaded and changed as the need arrises. I know it's a technology
just in it's infancy, but, hey, ALL this was not too long ago...