Do you keep all your unread books together, like books in a waiting room? Or are they scattered throughout your shelves, mingling like party-goers waiting for the host to come along?
This should be a short one. Generally my unread books are kept separate from the one's I've read. I have two bookcases in my living room and it used to be that one was for read books, and one for unread. But that changed as I got more and more books and now they are reserved purely for books I've read (and want to display)! My unread books are now kept in boxes in the bedroom, very roughly organised into the order I think I might like to read them, although this is obviously subject to change! And I have a pile of unread books by my bed, which are the ones I intend to read in the near future, but again, this doesn't always work out that way! And finally, there is always a large pile of library books waiting to be read, but they reside on a shelf in the hall, kept separate so they don't get lost in the endless boxes, and so that my memory will be jogged that they may need to be returned or renewed.
As usual, there is always an exception to the (very loose) rule, and that would be books in series, which would probably go on the shelves next to the ones from that series that I've already read.