Notebook.

For me Holy quran - it is part of my life .

aaaaaaaaaaaaaaahhh !!! º_º this is my worst nightmare turned into a question. I DON'T KNOW. I'm the crazy lady moving with a bunch of books in her hands all over my house ( when I move from one room to another ) I looooooove my books, and I dont think I could choose between them (the ones I already have and those I didn't read or know yet )

cheque book?

Whoa it's pretty awful, I don't dare to imagine that. Nevertheless I'd tell you my book's name: nature. Because it's a book that is hard for nobody to look through it during his/er lifetime.