So you're out in the middle of nowhere in a jeep (or on a plane). What about charging your recorder, laptop, camera, moviecamera, torch, etc. You could take spare batteries for everything, or get one of these
inverters for around 100 dollars. It also has USB power outlets to charge iPods, Blackberries, some phones. Haven't seen 220 volt models. Doesn't matter for most travel devices these days - 110 volts is fine.