Forget your charger again? Soon that might not be a problem. All you would need is an e-tattoo and a walk. Researchers at the University of California San Diego have created an e-tattoo—a very small, very thin, circuit board you apply to your skin like the temporary tattoos you are probably still sticking in hilarious places whenever you get the chance—that is on its way to harnessing the chemicals in your sweat and converting them into electricity.

Right now, the amount of energy that researchers are able to harness is small—not enough to power a wristwatch—but this is a significant step forward in terms of bioenergy and harnessing innovative sources of power. The chemistry that makes these e-tattoos possible has to do with collecting and repurposing electrons from the chemical lactate naturally produced when your body sweats. One odd downside to this process is that it definitely doesn’t encourage maximum fitness for maximum energy collection. The research subjects who worked out regularly produced significantly less sweat and therefore lactate than the subjects who were considered less fit.

The technology is in its infancy, but it’s hard not to speculate about its future. Imagine never having to worry about not being able to find an outlet. That’s a practical prediction; others, not so much. For example, did you know that Doctor Who’s Cybermen started making so many bio-mechanical alterations to their bodies that they eventually became emotionless, metal creatures? Could these e-tattoos be just the beginning of such a revolution for the human race? Or what if these tattoos, which have electricity running through them and are stuck directly to your skin, start to evolve on their own like the robots in Antonio Banderas’s new movie Automata?

On one hand, smart e-tattoos sound great. For example, doctors could address health problems quickly without the need for a patient’s self report. Of course, on the other hand, the authorities could use it to monitor drug use, alcohol abuse, and the physical location of everyone wearing one. Sounds a little Big Brother to me. Do you really want a tattoo that can potentially monitor you, affect your actions, and potentially change them? Sure, they determined that Scully and her pal Ed were under the effect of a hallucinogenic ergot in The X-Files episode “Never Again,” but I don’t want to take those kind of chances. I may be getting ahead of myself. Maybe.

Despite all the possibilities explored by pop culture—and the ways they completely terrify this writer—this potential breakthrough in biomechanics is awesome. E-tattoos have been around for a while, but powering them is a huge hurdle to making them more practical. If researchers can continue to perfect the way energy is collected from the human body (and they don’t tell the tiny computers about those perfections) maybe we’ll have an environmental breakthrough that could save the planet, and we won’t end up in a battle for humanity that involves a burned sky and humans grown in pods of red jelly. At least that’s what I’m going to tell myself.