Meals have long been served on ceramics—and now they're being used to slice food as well. Knives, vegetable peelers and mandolines with ceramic blades are the new must-haves in the trendiest kitchens. Kyocera of Japan and Boker of Germany make the ghostly white blades with zirconium oxide, which is second in hardness only to diamond. They stay sharp 10 times as long as steel and don't react with food or affect its smell or taste. They are also lightweight, making repetitive chopping less of a strain. The hardness of the blades makes them less flexible, however, so they aren't so hot for cutting that requires maneuverability, such as carving. And there's not yet a reliable method for home sharpening, so the manufacturer might have to put a new edge on for you when it finally dulls.