Throughout history, cultures around the globe have enjoyed the nutritional and medical merits of seaweed. In more modern times, these macroalgal plants’ diverse ecological properties have captured scientists’ attention. What makes seaweed so special is that it has special fibers made of complex glycan sugars that can be used to create anything from biodegradable plastic to sustainable cotton replacements. And being one of nature’s most abundant sources of these complex sugars, there is more than enough reason to explore the boundaries of what seaweed can be used to make. In Australia, two scientists have discovered that the compounds of purified seaweed extract is remarkably compatible with human cells’ connective matrix, meaning it could be used to create human-like tissue to help heal bone and cartilage damage in people. Now the scientists want to utilize a handheld 3D printer to replace cartilage in damaged knees with seaweed-based tissue. And if that’s not impressive enough, these same scientists are also spinning threads from seaweed extract and creating biodegradable plastic film using the stuff.