I also loved "Michael Clayton," a wonderful thriller that exposes the greed and short-sightedness of a giant agrochemical firm. It certainly fed my paranoia while making "Food, Inc."
On the documentary front, I loved a film by the Chinese-Canadian director Yung Chang called "Up the Yangtze." It is the story of a valley in China being flooded to create a dam. I wasn't sure if I was watching actors or real people. It turned out to be all real people who felt very comfortable letting the camera into their lives. It had a very theatrical feel. It is a beautiful film.