I watched Day Watch last night and the subtitles were interacting with the movie. One guy slashed his sword and it cut the subtitles in half, another person fell towards the camera and it crushed the subtitles over, one person cursed and threw a piece of raw meat against a wall and the curse appeared over the meat in red and splattered with it, another person knocked on the door and the subtitles pulsed with every knock.

They did stuff like that throughout the entire movie, it was BRILLIANT!!