MC, I also have the Twin Peaks soundtrack! Not "Fire Walk With Me" though, just the show.
Besides that, in my rare list (not counting local stuff or personal compilations) I have the soundtrack to Cheech & Chong's Up In Smoke (their finest movie), The Best of The Bonzo Dog Band, the official Disneyland album, Anthrax's "Attack of the Killer B's" (not terribly rare, but fun), Spike Jones' "Dinner Music", soundtracks to Encino Man, Tomorrow Never Dies, the Simpsons, South Park:BLU, Batman (the '89 Prince filmcan disk), Batman (the TV show), the Adventures of Ford Fairlane, the European CD Single of Garbage's title track to "The World is not Enough", and 2 Madonna CD singles - "Vogue" (it was a gift, but I kept it so I'm half to blame ) and the mini-CD "Like A Prayer".
The rest of my library is fairly routine Rock, Metal, a little rap, Cheech & Chong albums, SW, and etc.. I have a few interesting, rare tapes, but the only one I think worth mentioning is Sir Mix-a-Lot's "Baby Got Back" maxi-single which is actually a little stretched from all the play it got.