I knew there was some reason my mother named me "Geoffrey".
There are lots of other renditions on YouTube, but I like this best -- it gives you the text while they rap. This is just the prologue, but it gives us an idea how these wonderful stories could have been transmitted in an age of nearly universal illiteracy. (Thanks to Dirk for calling this to my attention.)
(To learn how it was done, check out RedYak.com. They do other stuff, too.)