When you don't have a lot of space to work with, sometimes you need a single room to fulfill multiple functions. These multi-tasking spaces all serve more than one purpose — but they do it in the sneakiest way possible, with hidden amenities like beds and desks that tuck away when not in use, so you'd never even know they were there.
Above: To accommodate three people in an apartment of only 409 square feet, the designers at Anthony Gill Architects created this bed in a drawer, which slides out from the bottom of a wall of cabinetry. (When not in use, the bed slides under the platform that you can see through the door in the left photo.)
This 640-square-foot Manhattan apartment, which is home to a family of four, has a dining table/workspace which folds down from the front of a bookcase and rests on a rolling storage cart. You can see more of the apartment at Dwell.
In this library spotted on Beyond Beige, what initially appears to be a very well-appointed card catalog is actually a Murphy bed which folds down to turn the space into a guest bedroom.
This pied-a-terre in Paris, a design of Batiik, has a dining table which folds out from under a countertop, revealing an unexpected bit of color (and a couple of stools, too).
From Homes to Love, a perfect solution to home office clutter, even in larger spaces: an office tucked away in a closet, with a door that slides shut to hide the workplace when it's not in use.
And finally, one more Murphy bed, from Magnolia, which turns this playroom into a guest room—and folds neatly into the wall when not in use, so you'd hardly even know it's there.