Oh, wow. Three five-shelf bookcases, loaded double where possible (books in front of books, books on top of books), three boxes of "to reads" that I can think of (might be four), about a dozen in the bed (in various states of being read), a bunch on the floor, and I don't know how many in my daughter's room.
About every two years she (the daughter) makes me sort through them but I don't give up easily. The only one I know I'll give up is Terry Brooks' Prophecy (somehow I have two copies)...
There is no such thing as too many books. Only too few shelves!