Slovenian architects OFIS have completed Tetris Apartments, a social housing development in Ljubljana.
Here's a little bit of text from the architects:
"The building stands on the edge of the 650 apartments development which was finished year ago. By urban rules the block is 3 floors high and 65 meters long. Since the orientation of the apartments is towards the car road the apartment areas together with balconies are orientated to the quieter south side."