The very first place i've been in Paris.
My first month in the city, i spend over 800€ in this bar (true story)
It's simple, warm and friendly, drinks are not so expensive (for Paris...). You can talk with every body, people there are open minded and funny (but only because everybody is drunk)
It's always good to check out what's happening in Fondation Cartier. They have lots of really good exhibitions of modern art, and the gallery itself is very beautiful. Perfect for seeing works you already know as well as discovering new artists and inspirations.