Shelf space needed!

Help!! I've run out of shelf space!! This is a recurring problem, I get attached to my books and cannot bring myself to either donate them to charity or add them to bookmooch. Some I will always hold onto to, but do I really need all the others? It might be time for an assault on the shelves and for some of the books to find their way to new homes, if only so I can see what I've got on the shelves when I'm looking for something good to read!!