Heidi Montag
Look up opportunistic climber and you'd probably find a picture of Heidi Montag. She was originally cast as the sidekick roommate to Lauren Conrad, who she met at 2004 freshman orientation at the Academy of Art University in San Francisco, on MTV's The Hills. But the blonde breakout quickly increased her screen time by increasing the drama. She dated and then married bad boy Spencer Pratt (eloped in Cabo San Lucas in 2008; made it official in California in 2009), threatened to breed, screwed up at her "real" job at event-planning firm Bolthouse Productions and had many epic and televised rows with Conrad, her hubby, her parents and other Hillsters. She attempted a singing career with her 2008 single "Higher," her record Superficial and 2011 single "Heartbeat." She exposed her own hills in Playboy in 2009 and then a few months later increased their size to DDD when she underwent a staggering 10 plastic-surgery procedures in one day. She had already gotten a nose job and breast augmentation in 2007. Speidi hit a rough patch in summer 2010 when she filed for divorce. They were back together in time to celebrate her 24th birthday and renew their vows in November. She attempted a reality comeback in 2011 when she joined the cast of Famous Food, a VH1 series that featured B-listers launching a new Hollywood eatery.