One of the best things about living in Paris for a few months is being able to go back to museums like the Louvre and the D'Orsay and really spend some time there.  Usually, when I am travelling, I make a mad dash through the museums and then on it's to the next place.  

The Louvre is open until 9:30 pm on Friday nights and since D was working late, I took advantage and spent a couple of hours enjoying it.  It is so vast!  I don't know if it is possible to see the entire museum even in multiple visits.  Plus, I usually end up people watching as much as anything.