I've seen closets with less storage space than the folding chair closet idea pictured above. Its versatility is undeniable. Add another chair or two if you need the space, and when you don't, or if you move and find you don't need an impromptu closet, you have extra seating. Another great idea is actually cutting one traditional chair into two for a closet/catchall that serves as probably the most interesting and ingenious coat rack I've ever seen. (Plus, you get two for the price of one.) Spotted at et cetera e casa.
Uma Cadeira [et cetera e casa]