"There's only one rule, and that rule is don't kill T-Pain," T-Pain said. He played songs like "Freeze," "Good Life," "Blame It," and "Bartender," He conducted the audience through a medley of covers ...

Based on the screams, you would have thought Taylor Swift actually did show up to Austin City Limits Music Festival. But it wasn't the world's biggest pop star emerging from a saloon-themed set.