The 27-year-old socialite - who recently claimed she has been single since splitting with Good Charlotte rocker Benji Madden - was spotted getting close to MySpace CEO Chris DeWolfe at Tao at the Sundance Lift in Utah.
A source told the
New York Daily
News newspaper: "They were grinding each other on the dance floor forever, before lying together on a banquette.
Then the couple began sucking face hard. They left out the back door, with her hand in his pants pocket."
Although a MySpace spokesperson refused to comment on the story, an insider at the social networking website said: "This is what happens when altitude affects your brain. They're just having fun."
Meanwhile, Paris is the star of a new sex tape, it has been claimed.
The hotel heiress - who famously romped with ex-boyfriend Rick Salomon in a homemade video - is seen "in a state of arousal in the back of a taxi", according to new book
Six Degrees of Paris Hilton
by Mark Ebner.
Ebner's book is the story of Darnell Riley, a man who took
Girls Gone Wild
millionaire Joe Francis hostage at gunpoint, went on wild nights out with Mickey Rourke and boxed with Rick Salomon.
Riley claims he bought 14 hours of video of Paris from two Russian kids who stole it when they broke into her home.
As well as the racy footage, there are also excerpts from Paris' grandmother's funeral in 2004.
Riley claims: "She is sitting in the church shooting video of herself. She is paying no attention to the eulogy. Paris has Brandon Davis film her when she gets up to say goodbyes to her grandmother."
Riley is now in prison on a plea bargain for extortion after he tried to blackmail Francis.