An anonymous reader writes with this excerpt: "A new membrane developed at the University of Rochester's Laboratory for Laser Energetics blocks gas from flowing through it when one color of light is shined on its surface, and permits gas to flow through when another color of light is used. It is the first time that scientists have developed a membrane that can be controlled in this way by light."
Never try to teach a pig to sing. It wastes your time and annoys the pig.
-- Lazarus Long, "Time Enough for Love"