This could be the end of old, rigid circuit cards.
The Laboratory for Soft Bioelectronic Interfaces at the Polytechnic Institute of Lausanne (Switzerland) has designed stretchable biphasic conductors that can be drawn out a million times until four times their length without losing their conductive properties. This quality resides in their constituent elastic material, a partly-liquid thin metal film (<1µ thick). Composed of a gallium-gold alloy with 400% stretchability, it can be integrated into polymer materials. Future applications are promising—from wearables and robots to artificial skin for prostheses.