I've added several new collection types in the upcoming Bookcase 0.8. Along with the collections of books, bibliographic entries, music, and videos, there will be default collections of comic books, coins, stamps, trading cards, and wines. I chose those because I want them. :-) There's also a custom collection where the user can add whatever fields they want, there just won't be specific icons or functionality for that collection type.
Right now, I'm going through and setting up the default fields for each new collection type. Anyone who is translating Bookcase will have a bit more work, but these should be the last that I add.