My grandpa told me the in the 1920's and 1930's, many cartoons would feature music that sounded quite a bit like modern rap-music. It had quick rhyming and the cartoons would do strange little dances and whatnot. He said that this was common at the time. I'd be interested to know if you have come across anything like this. I've searched youtube and google, but have not found what I am looking for. Any ideas on where to look?