If you have an old step ladder that may be beyond using Action pig over on instructables has a tutorial on how to spiff it up and adapt it into a book shelf. I love ideas like this that re-purpose things that might end up in landfill into something usable. A pair of these would be nice on either end of a sofa in the basement or even painted to match a bedroom.
Ladder Bookshelf diy
Altra Furniture Metal Frame Bundle Bookcase Ladder, Black, Set of 2
Winsome Wood 3-Tier A-Frame Shelf, Black
Black Ladder Shelf Storage with Wine Rack (3 Piece Set)