I made 2 sets of curtains to cover up the lower 3 shelves of our bookcases. I'm not a huge fan of open storage. I love the look of it, but when it comes right down to it, looking at too much stuff makes me feel a wee bit claustrophobic. Thus the curtains.
I used fabric from Amy Butler's Nigella line on the top, and a painter's drop cloth for the bottom. (I saw the idea of using a drop cloth for a curtain here first). They were a simple project to sew and I love the way they turned out.