Michael Richards (Kramer from Seinfeld) lost his temper during a stand up comedy show. Here is his video on David Letterman.

http://www.youtube.com/watch?v=dufHYw-W6j4

There is a video from the actual event. It's pretty bad.

I saw the clip from the show when the thing went off. Pretty crazy, but he sounds sincere about it. The african-americans came back with racial slurs at Richards after Richards initiated it, so they need blame as well. And Chris Rock would have said the same thing probably had it happened to be two african-american hecklers. Doesn't make it right, but still, it's a spur of the moment type of thing. He shows remorse so I think he should be forgiven.