In recent years, researchers have created early versions of "invisibility cloaks" and advanced optical fibers by manipulating light using structures composed of tiny, repeating units. In the 9 April Physical Review Letters, a team proposes a different way to make an artificial optical material--from a network of light-guiding filaments. If such structures are practical, they could open new ways to control light in technologies ranging from high-speed telecommunication to high-resolution imaging.