Joseph Gordon-Leavitt, probably best known for his lead performance in Brick (great movie, by the way), was accosted by a couple of paparazzi, and responded in a way that most people could only dream of - he takes out his own video camera and shoots back. Then he goes and engages the two of them in conversation, completely against their will. It's fascinating to watch him peeling away the evil shell and get close to humanity. (Bad language warning.)
This is a clip that's stayed with me long after my initial viewing; I'd be interested to hear what you think.