27 Ways To Rethink Your Bed: Bed in a Closet. Also check out the Roll-Away Bed under a Platform; Cool way to quickly tidy up a small space, and keep pet hair off the bed! Maybe put a little reading or office space on top on the bed?
built in bed as piece of furniture with wardrobe at foot of bed. Love the hanging curtains so the child can close them for privacy or a fort / clubhouse feel (Good idea for guest room when there's no space for an actual guest room)