In the mid-90s a book of homebrew musical instrument projects was published called Sound Designs, by John Scoville. Amongst the scores of awesome ideas within, the book suggests making hanging bells by cutting apart discarded gas bottles. There’s surprisingly little information about this trick on the web. This page, though an oldie, is still a goodie. The author discusses the tricks for cutting the bottles and the resulting tones from several bells. You can even listen to what they sound like.