Developed by researchers at the University of Colorado, a new concrete alternative could provide a carbon-free option for buildings in remote places—where lugging traditional concrete ingredients proves difficult. Only two components—photosynthetic bacteria and gelatin—make up this “living” concrete. Due to its photosynthetic nature, it starts off green before drying into a brown hue. Perhaps most impressive of all, the concrete can regenerate: “When half of a brick is mixed with additional nutrients, sand, gelatin, and warm water, the bacteria in the original piece can grow into the added material. In seven days, the scientists had two bricks instead of one. They repeated the test several times to show that the bacterial bricks could be used for exponential brick reproduction, eventually creating eight bricks from the original,” according to Smithsonian Magazine. Learn more there.