J.K. Rofling
A fake laugh that happens when you tell someone a Harry Potter secret and then act like it was the funniest thing ever.
You told your friend about the prophecy before the book came out and then rolled on the floor like a mad dog.
You ruined the surprise of the final book and then laughed like you were high on candy.
You leaked the final battle and then cackled like a witch on a broomstick.