With the Mophie Keychain Charger, you get a great charger that doubles up as a keychain—essentially taking very little space in your pocket. This lightweight device from Mophie will provide your iPhone with a battery boost of up to 50%, and it works with both iPhones and iPod Touches. It won’t work with older models of the iPod, but it’s not like anyone uses those anymore anyways.
You can pick one up right away on Amazon for under 30 dollars, and it’ll even come bundled with a built-in USB cable so you won’t need to lug around any extra cords.
Source: Hiconsumption