I'm into physical books and as a result of that I have a rather large bookcase in my living room. The books are sort of ordered by type (literature, foreign lit

I'm into physical books and as a result of that I have a rather large bookcase in my living room. The books are sort of ordered by type (literature, foreign literature, non-fiction, etc), with some space in between. 'Unread books' is a separate type. Whenever I feel the urge to buy something new, I check the physical space the unread books take up on the shelf. If they extend beyond a totally arbitrary limit that I set for myself, then I have to wait and read some of them first. Works very well for me.