Told to one who will not shut up, or one who has just made an off color or unfunny joke at an inappropriate time.
Professor: Open your textbooks to page 594.
Student 1: Haha! Snape kills Dumbledore on page 594!
*Students stare*
Student 2 to Student 1 (loudly and rudely): Go wait in the car!
Professor: As I was saying--
Student 1: Haha! Snape kills Dumbledore on page 594!
*Students stare*
Student 2 to Student 1 (loudly and rudely): Go wait in the car!
Professor: As I was saying--
by Fairyland June 16, 2007
Get the go wait in the carmug.