Don't take one book take several!
Use something like
mobipocket and download any book that takes your fancy.
There are numerous free sites like
Project Gutenburg where you can download over 28,000 books including
Moby Dick. On my PDA I have 15 books at the moment, including the 'Decline and Fall of the Roman Empire' by Edward Gibbon; now I would hate to have to carry the hard back version of that book around with me.
Downside is that it is not easy to read in sunlight; upside, great in the dark!
I use a wind and solar charger to keep the PDA charged and also get a phone and internet access with it.