Curtains are not just for windows. In a room where there are not enough windows, you can use window curtains to create a design element. While they may just be covering up wall space, guests who enter your home won't know the difference. You can also make a small window appear larger by buying window curtains that are larger than needed. For example, if you have a small window on the upper wall, you can add floor length drapes to give the illusion that behind the curtains the window is longer than it really is.