You: I like Tacos. Wait, what?
Dude 2: Oh, really? Where at?
Dude 1: On cops, they busted her for prostitution.
Dude 2: Oh, that's nice. Wait, what?
2. Used to deflect personal responsibility from a blunt comment.
Girl- "Uh, excuse me?"
Me- "I don't know what you're talking about..."
2. Me- "Why don't you quit being such an asshole? Wait, what?"
You- "What the hell did I do?"
Me- "Um, I was just joking?"