Shurap is a skilled YouTuber and also a blacksmith by trade who has found a way to recycle old batteries. He converts these old batteries into fine knives. The Damascus-steel knife uses a Maglite flashlight for its handle.
DO NOT TRY THIS AT HOME, If you still want to try this then do wear on a pair of rubber gloves before you try to pry out the metal in the batteries as it contains highly-caustic materials that can harm the skin in case of direct contact. Check out the video below.