The Palais de Tokyo, an art deco building that dates from 1937, reopened in 2001 after a new interior design by French architects Anne Lacaton & Jean-Philippe Vassal who selected rough and ready style (concrete floor, wall and roof).
Today the most creative and fun museum in Paris, the only one to be open till midnight. The Palais de Tokyo, which is right next door to the Musée d'Art Moderne at the Trocadero, has opened as a showcase for contemporary art. The idea is to have no permanent collections, but to let experimental artists have somewhere in central Paris to express themselves, hence an opening full of “installation” and “interactive” art.
There is no permanent collection; instead, dynamic temporary exhibits spread over a large, open space that's reminiscent of a construction site, with a trailer for a ticket booth.
http://www.paris-paris-paris.com/paris_landmarks/museums/palais_de_tokyo_paris