If you’re lost in the woods and your flashlight batteries run dry – as Keanu Reeves would say – “What do you do? What do you do?” Well, you can start by taking a piss. Seriously.

Yes, the NoPoPo (non-pollution power) Aqua Battery will run off water – and pretty much any liquid for that matter, including urine. The NoPoPo works simply by inserting liquid into the base with a teat pipette. The batteries will also run on beer, saliva, apple juice or coco-cola. Unlike standard batteries, the NoPoPo doesn’t contain harmful substances, such as mercury, hexavalent chrome, lead or cadmium, so you can dispose of them without thinking twice.

These rechargeable batteries come in AA and AAA and are charged by a mixture of magnesium and carbon that reacts with the liquid you choose to inject, which in turn produces up to 500 mAh of life.