Paris museum tips

If you’re going to see more than one museum, it’s well worth buying the Paris Museum Pass.  Not only is it cost-efficient, but many of the museums have pass-holder lines that may not be well-marked, but always MUCH shorter and worth asking for. You can buy the Pass at major metro/train stations, Paris Information kiosks (there's one outside Notre Dame), or at a museum (I get mine at Musee de L’Orangerie, where the line is usually short).

• The Louvre is open late on Wednesdays and Friday at a reduced rate. Go then, or go first thing in the am AND use your pass to skip the line at the pyramid entrance.  Instead use the "secret" museum pass entrance in the Richelieu Wing:  assuming you took the Metro to Palais Royal/Musee du Louvre, exit and face the Louvre, cross Rue de Rivoli and turn LEFT and walk along Rivoli until you encounter a gated archway - the entrance is on the right under the arch. Most people walk through this archway to the pyramid and never notice the museum entrance on the right, but there it is: brass stanchions, velvet rope, glass security booth. Flash your pass at the security guard and he'll wave you in. You can always have your pyramid experience as you exit the museum, but the lines to get in can be horrendous. The Richelieu entrance is insanely fast.
• The D’Orsay pass entrance is to the right, around the corner, of the main entrance.
• Musee Rodin is a good pit stop between Napoleon's tomb (Hotel des Invalides) and a St Germain des Pres cafe. If you're not up for the whole museum tour, you can just swing through the pretty sculpture garden. 
• The Picasso Museum makes a good excuse to visit the Marais, but is sadly closed until 2013 for renovations.  
• Have I mentioned lately how much I love Musee de l'Orangerie?  Read more about why here.