The World’s Narrowest House [is 60 inches wide] - Warsaw, Poland 2012 - by Jakub Szczesny
Inside The Keret House - the World's Skinniest House - by Jakub Szczesny
Worlds Thinnest House: Keret House by Jakub Szczesny, Warsaw
The World’s Narrowest House in Poland
Dom Kereta house "In the crack between the buildings on 22 Chłodna St. and 74 Żelazna St., Jakub Szczęsny designed an art installation entitled Etgar Keret's House, which shall become the narrowest house in Warsaw, since its interior will come to 133 centimeters in the widest spot."
Thin Apartment Building, Italy Old three-storey building from the picture still has tenants, judging by arranged balconies. This thin structure is probably located in some old neighborhood in the Italian province of Caltanissetta on the island of Sicily.
The Flatiron Building, NYC--Daniel Burnham, architect. I think this is my most favorite building in New York. I never tire of seeing it sail like the prow of a ship, right up Fifth Avenue
Sliver Building, Tokyo, found via The World Geography - "In overpopulated Tokyo, where each square meter has a very high price, buildings such as this one are not at all something unusual. Building from picture has 12 floors.