One thing we learned from superstorm Sandy: People really, really rely on their cell phones. When the power goes out and you can’t recharge, it’s like being cut off from the world — which includes being cut off from critical help and information. Now that we’ve seen how eco-disaster can knock out power for weeks in the country’s most populous city, our idea of “emergency supplies” might expand beyond canned goods and water to include one of these cell-charging innovations.

Fire-powered chargers

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These are spendy, but they have one advantage over other cell-charging solutions: You can cook soup in them. The BioLite CampStove uses heat from whatever you burn (twigs if actually camping, maybe newspaper if you’re just trying to get by in Lower Manhattan) to run a thermoelectric generator, which powers both your phone and a fan that feeds the fire and makes it more efficient. Some NYU students set up a charging station with four of these things last week. Was it better than huddling in an ATM kiosk? Well, it had more soup.

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Hand-cranked chargers

Etón’s hand-cranked USB jack isn’t the most efficient way to get cell power — it takes a minute of cranking to generate 30 seconds of phone use. If you want to chat, tweet, or check Tumblr, you’re going to end up with Popeye forearms. But it costs $50, making it a fairly reasonable addition to your emergency kit, and that 30 seconds of power will get you an emergency call, a few texts, or a map to the nearest shelter.

Knee chargers

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If you’re in the Canadian military, you may already be using these brace-like chargers, which power devices using the energy you produce while walking. The PowerWalk M Series weighs 1.7 pounds and can charge four phones with an hour of walking. One problem: As far as I can tell, it’s not available to civilians. Another problem: It sounds like a school bus full of monkeys.

Solar bikini charger

Don’t judge.