Yesterday, I got out of the first third of my novel. Okay, I technically may have passed it the day before but I'm counting it as yesterday because my characters have now left town. For the first time in my novel I am describing bog and swamp, talking about bandits and weaponry, rather than courtesy, sisters and ex-lovers. It really feels like my novel moved into a whole new world.
So I guess that's some advice to take with you novelling... if you feel stuck, send your characters someplace they've never been before. It can add a lot of new life to a piece that you feel a bit stuck on.