What do you do if you need windows—lots of them—but your country also happens to be in the Ring of Fire and therefore prone to earthquakes? Use oyster shells instead of glass, of course! The Placuna placenta is a mollusk found throughout Asia, particularly in mangrove swamps. You can see almost anything made of capiz, or kapis, in the Philippines, but best use has always been the large wooden windows found on traditional houses and buildings. The key is to keep the windows closed during the daytime, keeping the sun out, and then open them wide at night to draw in the evening breezes.