24 "rooms" in 344 Sq Ft - "“Domestic Transformer" by Gary Change

This was featured on a segment of television show called World's Greenest Homes
and it is by architect Gary Chang who lives in Hong Kong where housing space is very limited.  The space apartment above was where grew up with his parents, sisters and another tenant and he now lives here.

He achieved the different living areas by putting the efficiently designing vertical units that are in a tracks in the ceiling and wheels on the bottom of walls so that can be moved to create 24 different "rooms"  along with a fold out bed and tables.   To hide the tracks in the ceiling and make the room look bigger, he has mirrored tiles on the ceiling. 

Found via Neatorama