We live in a technology-dependent culture whether we like to admit it or not. For years, when the power went out... which happens a lot out here in the country where we live... the good 'ol trusty telephone still worked because it had a separate power source from Ma Bell. These days, we don't even have a "land-line" any more as it was dropped when my daughter was finally provided a cell phone several years ago.
While I've talked about back-up power before, sometimes you need a quicker or more portable solution for your technology, a lot of which can now be charged via a USB port. First of all, make sure you pick up a USB adapter for your vehicle's cigarette light, which can usually be found for less the ten bucks.
Another solution, which is quite inexpensive, is a battery-powered back-up USB power source. We picked up several of these Rayovac 7-Hour USB AA-Battery Powered Chargers for less then ten-bucks each a whole back and they come with a set of four AA-batteries. I've tried one of ours and it actually lasted for almost nine hours of continuous use on a discharged cell phone, which it did bring to a full charge.
I also purchased one for my daughter who is away at college and has already experienced an eighteen-hour power outage. Keeping those iPhones, iPads, iPods, and iWhatevers charged is critical in an emergency, so for anything short of the zombie apocalypse... pick up some... Back-up USB power for your technology.