As a birthday gift yesterday, MAKE: Blogger Phil Torrone received this excellent wall vase made from a spent shotgun shell and a suction cup. Link
UPDATE: BB reader Deadprogrammer writes in, "During and after the two World Wars artisans made a mind boggling array or vases, lamps, pens, lighters and who knows what else from discarded shells. Some are very beautiful, executed in Art Deco, Art Nouveau and Craftsman styles." Link to eBay search