From PEOPLE Magazine Click to enlarge
Nicki Minaj VS Mariah Carey

With two divas on the same American Idol judging panel, drama was inevitable. Still, when Minaj, 30, went on an expletive-laden rant against Carey, 43, during October auditions, the mom of two decided to hire extra security. Now? "We jelled really, really well as a group," said Minaj.

Madonna VS Elton John

John, 65, loves to bash the Material Girl, 54. In January he said she had no chance of winning a Golden Globe and, six months later, called her a "fairground stripper." Madonna was unfazed: "I forgive him!" she said.

Chris Brown VS Drake

A June nightclub brawl pitted the singers and their entourages against each other (both Drake, 26, and Brown, 23, have been romantically linked to Rihanna). Who started the dustup-which injured five people-remains in dispute.

Jon Hamm VS Kim Kardashian

After the Mad Men actor, 41, called the reality star, 32, an "idiot" in an interview last spring, Kardashian tweeted that his words were "careless." So was it awkward when they saw each other at a 30 Rock taping a month later? Nah. Reportedly they laughed it off.

Brandi Glanville VS LeAnn Rimes

Glanville, 40, has two sons with Eddie Cibrian, to whom Rimes, 30, is now married. Coparenting seemed to go well until December, when Glanville tweeted that Rimes was "trying 2 get under my skin by calling MY children 'her boys.'" Retweeted Rimes: "Stepmoms don't replace, they add to."