One of the strangest buildings in the world is the Krzywy Domek an irregularly-shaped building in Sopot, Poland, that makes you feel as if you're passing through the hall of mirrors in a funhouse. Built in 2004 the Krzywy Domek, whose name translates into English as the "Crooked House" is 4,000 square metres in size and is part of Sopot's Rezydent shopping center.
It was designed by Szotyńscy & Zaleski who were inspired by illustrations found in fairytales. Here's link to the site.
Photo: Broca