I have seen a lot of cell-phone batteries before, but this particular one by Voltmaker recharges with something that is very easy to access: kinetic energy.

The Voltmaker is very simple to use as you simply take it out and spin it like a nunchaku. It weighs about 10 ounces, and has a length of 6 inches, so it looks like it can fit in your back pocket.

So even though you are out in the middle of nowhere, you can take out the Voltmaker and spin it for two minutes in order to power a telephone call lasting several minutes. You can also just charge it on the wall outlet if you have access to that, too.

This is an Indiegogo project, which means it needs your funds to make it a reality. You can get it for about $69 or $89, if you want the flashlight attachment.

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