Fuel Micro Charger

You can get extra power from a big battery that straps to the back of your phone — but if you prefer to use your phone "naked", the Fuel Micro Charger ($25) is a good thing to keep around. This keychain-friendly device looks like a rusted fuel can — literally — and rocks a micro-USB port that you can use to access and/or charge the 220 milliAmp battery, which is good for about 20-30 minutes of extra juice. So no, it's not going to get you through a full day of bad service — but it might be just enough to get you out of a jam.

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