In reply to alexjz:
As others say, you can have a lot more fun climbing around, doing circuits, finding problems that suit you than trying to find specific/famous problems.
That said, Big Jim (6c, high wall on pockets) at Petit Bois is worth seeking out. I also like Surplomb de Marbre and the arete next to it at Buthiers (6a/b); Duroxmanie is really good too (as are thousands of other problems). I think Franchard Isitis is a must-go-to venue, and you'll quickly find the best problems for you, there are loads (Le Statique is the famous easier one, but it's not a nice problem IMO, just a cool looking feature).
My general advice is always to go somewhere a bit off the beaten track, and try climbing a slab. After a few days on the polished/poffed to smithereens stuff, you'll be amazed how much easier and fun it is when the rock isn't trashed. You don't have to fall off the same foothold 2000 times.