The relationship between advertising and music has never been stronger, and Melissa Etheridge has a pretty good idea where it began.

At Wednesday night's (Oct. 1) CLIO Awards -- honoring the year's best and most creative advertising -- the rocker took the stage to present the Grand CLIO Music award and introduce the night's two musical acts, X Ambassadors and Salt-n-Pepa. But she couldn't leave without offering up a little music of her own.

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"Have you been good?" she asked the crowd at New York's Museum of Natural History. "You're good, so I will leave you with one little musical thing."

Then Etheridge broke into an impromptu cover of Janis Joplin's "Mercedes Benz" while the room of advertising execs clapped along. Yup, Joplin knew all about cross-promotion way back in 1970.