Tonight, on the Money Programme, we're going to talk about money... I always loved money...
Okay, seriously, I'm thinking about all the forms currency can come in, and for some worldbuilding stuff, I'd like ideas on what can be made into currency.
In one of my settings, I've got a chain of islands where the natives have learned the art of farming pearls. One form of currency comes in the form of rectangular pearl tiles with a hole in one end so that the tiles can be threaded together with a string. They've been known to snicker slightly when a foreigner wears it as jewelry.
Of course, pearls would probably be one of the upper tier, like gold or platinum, so I'd like ideas for what a culture with relatively little metal to work with could use for pennies.
Any other interesting forms of currency are welcome in the thread. I'll be skimming Wikipedia.