man, I was just having this conversation, except about movies, with my roommate. He got seriously angry at me for saying I hadn't seen the Princess Bride.
Anyways, I haven't ever listened to Velvet Underground, despite lots of recommendations from my friends. Ditto with the Eels, and deerhoof. And I don't think I can name a single Clash song besides London Calling that I've ever listened to, along with anything by the Ramones. And I'm sure there's way more.