These stars don't stay single for long!
Despite once being engaged to Greek shipping heir Paris Latsis, reality star and socialite Paris Hilton, 30, has dated everyone from Backstreet Boys singer Nick Carter to Hangover II director Todd Phillips. (Other loves include model Jason Shaw, Greek shipping heir Stavros Niarchos III, Good Charlotte's Benji Madden, The Hills reality star Doug Reinhardt and nightclub owner Cy Waits.)
Notorious heartbreaker Justin Timberlake, 30, has been linked to some of the hottest women in Hollywood, including Britney Spears, Jessica Biel, Cameron Diaz, Ashley Olsen, Jenna Dewan, Fergie, Olivia Munn, Scarlett Johansson, Alyssa Milano and Olivia Wilde.
Unfortunately for Timberlake, Wilde isn't looking to be tied down. After divorcing Italian prince Tao Ruspoli in March 2011, the Cowboys & Aliens actress, 27, has also been seen out with Bradley Cooper and Ryan Gosling.
For more of Hollywood's biggest flirts -- including Amanda Seyfried, John Mayer, Taylor Swift and more -- check out the gallery now.