If you have been to Paris several times, you probably already know the Louvre Museum, Orsay, Branly etc...all these cultural places but have you ever considered going to a hotel for a cultural moment?
It is true that art is widely spread in Paris. Have you thought of going somewhere where you wouldn't usually go when looking for art?
There is a hotel called Hotel des Academies et Art, in the 6th arrondissement. The owners are crazy about art: a video art screening room displays audiovisual exhibitions from video artists, a white giant appears on the red-painted wall of the inner courtyard etc ...
It's very cool and the staff would definitely let you step inside to have a look.