I once saw a very mousey white guy get up from drinking alone at the bar, cooly walk up to the mic, lay down the most amazing rendition of "Sex Machine" I've ever heard, put down the mic, and walk back to the bar for a drink.
In the middle of the performance, a black guy got up from his table, draped his jacket over the guy like a cape, and the dude didn't even break character for a second.
The guy never sang again or got up from his chair again all night. It's on the list of the most bad ass things I've ever seen.