This is one of the oldest "filks" out there. There are, perhaps, thousands of verses. Joe Bethancourt keeps a nearly complete archive of all the verses at http://www.whitetreeaz.com/vintage/realotr.htm

If you don't know what filk is, then count yourself lucky. Or, if you really must know what its all about, go to a science fiction convention in the middle of the night, and find where the guitars are. All are welcome.