A good way to prepare for this problem is to collect phone books and similar type books. Where I live you can literally pick up stacks and stacks of free phone books in various stores (the yellow page variety). For some reason companies still produce these but nobody wants them because they just use their iPhone for info. Phone book pages are very thin and could double for toilet paper (although it probably wouldn't feel as cozy as your charmin brand) and it also provides a host of other services (fire starter, insulation, etc).

I've never heard of the tablet though - interesting concept.