Need more floor space? Book shelves hung the length of a room at ceiling height will help with that while giving you a place for your books as well as display space.
No room for a nightstand, a deep window sill can take its place. Love the blue and white color scheme.
Floor to ceiling shelves are another great idea, and if deep enough could also be used in place of a desk. Love the chandy.
I have actually used the next idea in one of my previous homes. A desk can do double duty as a nightstand.
Layering shades and gauzy curtains gives a wonderful light and airy look to a small bedroom.
All of these ideas and original photo credits can be found on Apartment Therapy.