Does your cat ever get angry?

I've got three cats. My oldest, Casper, is usually a calm, docile cat. But once in a while he will get angry at the other two for no reason. I've come into a room in the house and find that he's backed one of my other cats into the corner. He's got his ears held back in that don't-you-even-think-about-moving-from-that-spot position. It's scary to watch. I break it up all the time, but I wonder what it is that sets him off like that.