Someone told me once that they were going to put 3 teakettles on the stove for an experiment. They would put liquids in all 3 and make sure the liquids were all different in terms of "thickness". Water, milk, soda, etc.... so as to get different sounds.
They would do this and, once they started boiling and that flipper lid thing started whistling they would alternate the heat under all of them so he could vary the tunes coming out of it.
I think he lost interest and never did it, but if anyone gets bored and wants to try it, post the results here.