I went to the Pompidou center and toured their main exhibit, an overview of 20th century art called "Big Bang", organized thematically. There was lots of interesting stuff, but it was very big and very full, thanks to free admission today (the first Sunday of the month).
One of my favorites was "Five Angels for the Millennium", with 5 films projected in a very dark room--it took a moment for your eyes to adjust to the point where you could really even see the films well. I was also amused to see one of Bruce Conner's dense labyrinthine ink things in a section under the heading "ivresse", together with a copy of Howl and some random stuff by Patti Smith.
For lunch I had a baguette sandwhich sitting next to a nearby fountain.
I also found a reasonably convenient and inexpensive place to hook up my laptop nearby. It was oddly primitive--for example, they didn't have a dhcp server set up for some reason, so you had to manually configure the networking based on a piece of paper stuck above each desk.