It depends on how much interest I have in the presentation. For example, at a rockets game, when I see a great play unfold, I'm the first to scream "yeah!" or "There it is!" or "nice pass/shot" etc. However, if I'm attending something where I don't give a damn, I'll either be a second clapper or no clapper.
i hate the idiot that always wants the last clap...usually clapping one final time after everybody else finishes
I like to clap in the movies when something cool happens like Yoda poppin out the light saber, Harry fighting off dementors, or Mr. Frodo saves the ring from being taken by the bad guys.
I love the homeless people. Most of the time. Ok. I like females that make it clap. That's hot. I like to be the last to stop clapping. I like to last a good five seconds after everyone is done clapping.
I clap at different scenes during High School Musical. It's on now!!!!!!!!!!!!!! The first and second one back to back.
I like to clap earlier than is necessary and get the people not paying attention to clap-catch-up. Works great during boring speeches.