A sarcastic remark saying you don't care. Usually said after someone says something incredibly stupid or random. It originated from the movie "Arthur" where Arthur tells his valet, Hobson, he's going to take a bath. Hobson, not caring, says "I'll alert the media."
Arthur: Hobson
Hobson: Yes, Arthur
Arthur: You know what I think I'm going to do?
Hobson: What, Arthur
Arthur: I'm going to take a bath Hobson: I'll alert the media...