Dish! What Makes Someone Funny?

Some people have a dry sense of humor, some are animated and loud. I can't really say I have a type, but like art, I know it when I see it. And you can see from my IM exchange with a friend up there about a mutual acquaintance, I don't like when you can tell someone's trying hard to be funny. What qualities make someone funny to you? (And don't mind those catty cats up there! They're always like that.)