In the Yap Islands in the South Pacific it can be a stone with a hole in the middle. It can be a string of shells, a bundle of cloth or a copper slab. Some people think it's wonderful; others that it's really, really bad. So what is it? Money, of course. The stuff that makes the world go round. That doesn't grow on trees. That can't buy you love, apparently. Once upon a time there wasn't any, so why would anyone have gone to the trouble of inventing it?