If you are watching movies then have probably seen already someone hiding something in a hole carved in book. The idea of hiding something in book is pretty old and it is questionable how it is efficient to hide something in book because, everyone will probably search for something in there. But if you need to hide something in your living place and you have a shelve fool of books then your chances are better, since the eventual thief have to check all th e books on the shelve in order to find the secret one. We know that the most of thieves do not like to read and some even to touch the books, especially when there is a full shelve of them so your hidden things should be pretty safe in there.
Now you just need a proper book to do that. Well, if you believe that the job of hand-carving a hole in your thick book, the group of designers which call themselves Black Sheep & Prodigal Sons have made a book-box called Dark Miracle Box.
Dark Miracle Box will indeed be a small miracle in your library. Made from ebonized hardwood with security lock, it should be enough safe to store some money in there. However, this seems to be limited eddition and there are only 50 of these produced but the makers of this thing claim that they have intention to make another version of The Dark Miracle Box.