two examples:

When Nettrice & I saw Black Sheep, the film opened with an ad for that beer, Stella Artois, that was one of their fake short films (why an ad during a film festival is a whole separate question). At the end of the ad, our film festival friend Jason (www.jasonwatchesmovies.blogspot.com) hollered "Brrrrillliant!" It was well timed.

Or when I saw a trailer for that movie a few years ago about recording ghosts' voices, whatever the hell that stupid movie was called, the trailer was really deliberately scary. And at one point during the trailer, someone in the theatre let loose with a blood curdling scream, better than I could have done with months of practice.

Again, beautifully timed.

During the movies, no. Sit still and stfu.