Michelle raved about this book, City of Ember, so I read it. (I didn't love it as much as she did). Now there's a movie, and here's the teaser trailer. Starring Bill Murray, Tim Robbins and Saoirse Ronan. It looks pretty good, actually.
Keep an eye on Saoirse Ronan. Between Atonement, City of Ember and The Lovely Bones, I'm thinking she's probably the best child actress out there right now. Way better than Dakota Fanning.