the musical equivalent of only knowing "Stairway to Heaven" by Led Zepplin... which is the only Led Zepplin song I know. Ahem.

Aha! I have one up on you. Not only do I know "Stairway to heaven", but I also know that Led Zeppelin song that goes "do-do-do-do Do-DO", you know that one where Robert Plant is screeching like a spring windstorm blowing down from the Cascades and it has that fiddly, self-indulgent guitar bit in the middle, AND the one that mentions Gollum from the Lord of the Rings.