Originally Posted by ApK
Speaking for myself, I would prefer swappable batteries. True there other ways to extend life on a trip, and I like those options, but they all involve carrying another piece of equipment, as does the carrying of a spare battery, but the swappable battery would be fastest and most convenient.
A device like this is a pretty good alternative:
It will provide about 2 full charges for my Kindle from a set of 4 AA batteries.