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.

On the night of January 17, Larson was spotted entering through the back door of Hollywood Life House, and after she had a few drinks, she was seen provocatively grinding half a dozen guys on the dance floor.

She was so caught up in the moment that she even had her legs wrapped around a gentleman's waist.

Larson's evening ended with her then leaving the place with Ashlee Simpson's ex-beau Ryan Cabrera. (ANI)