Temporary tattoos can be a fun, fashionable and cost-effective promotional product, giving people the license to change their look with a whimsical design or show off brand loyalty without permanently altering their appearance. In the future, however, temporary tattoos could serve a higher purpose than just aesthetic. Researchers at MIT’s Media Lab recently created jewelry-inspired gold leaf tattoos that turn the skin into circuitry.

“I think there is no fashion statement greater than being able to change how your skin looks,” says researcher Cindy Hsin-Liu Kao, lead developer of the DuoSkin project. “These tattoos enable anyone to create interfaces directly on their skin.”

The DuoSkin tattoos come in three varieties. There are input devices, which are tattoo touchpads that allow you to control your music device by swiping or tapping your skin. Output devices turn the skin into a display, using thermochromic pigments that change color based on body temperature. Kao gives the example of a fire tattoo that lights up based on the wearer’s emotions. The third type of tattoo is communication-related. These tattoos act as near-field communication (NFC) tags to enable data exchange. NFC tags are a great way for brands to connect end-users with bonus content online, helping promotional products generate even more lasting impressions.

The tattoo concept is accessible for just about anyone, according to Kao. Would-be designers sketch out skin circuitry using any kind of graphic design software, create a stencil of the circuitry with an inexpensive vinyl cutter, apply gold leaf as the conductive material and mount the electronics. The finished tattoo is applied through water transfer, the same as ordinary temporary tattoos. “Where I’m from in Taiwan, there’s a huge culture of cosmetics and street fashion that’s highly accessible and cheap; you can easily change and edit your appearance whenever you want,” Kao says. “We purposely wanted to make [DuoSkin] accessible for anyone.”