Washington, Jan 22 : Former cocktail waitress Sarah Larson, who once dated actor George Clooney, was spotted grinding with a couple of men at the Sundance Film Festival during the weekend.

Larson was seen cavorting around Park City with a number of Sin City boys, and her behaviour at the Hard Rock Hotel & Casino Las Vegas after-party for the flick "The Vicious Kind" caused quite a stir, reports Fox News.