The Rocket Man's long-standing feud with the Material Girl began in 2004 when he accused her of lip-syncing on her Re-Invention World Tour. "Anyone who lip-synchs in public on stage when you pay $134 to see them should be shot," he said at the time.
Though fans might have assumed that pair had buried the hatchet, Elton dissed Madonna's 2012 Golden Globe-nominated song, "Masterpiece." When Madge eventually took home the award, Elton's husband David Furnish lept to his spouse's defense, sounding off on Facebook ("Madonna. Best song???? F**k off!!!") and to the New York Post. "I think it was a fluke," he said. "Can you sing Madonna's song? Can you hum it? It's a song nobody has heard, from a film few have seen. The award should have gone to (nominee) Mary J. Blige or Elton."
In 2010 Neil Patrick Harris was none too pleased with actor Eric Braeden, who was set to guest star on "How I Met Your Mother" but pulled out before shooting.
Harris tweeted "Eric Braeden is a D-Bag. the actor, (Robin's dad) agreed to a cameo, then last night bailed, saying the part wasn't 'substantial' enough."
Braeden responded to the controversial tweet via Entertainment Weekly. "First of all, I came back from hip surgery. I was off for three weeks. I've doubled my work, 30 to 50 pages a day for me, alone. Everyone knows that I'm exhausted. I was not about to appear on a show for two lines, because that's what it amounted to," adding, "It seems to me like a young whippersnapper, having seen himself on a few covers, who's received a few awards, is now suddenly suffering from the first signs of hubris. I've been in the business for 50 years. I've seen people come and go and I'm still here."
Harris expressed some remorse for his statement and three hours after his first Tweet when he then wrote, "Now I feel bad for the D-bag comment. Don't know the guy personally. I'm just fiercely protective of our show."
It was no laughing matter when "Grey's Anatomy" actor Washington referred to co-star Knight as a "faggot" during an on-set argument with Patrick Dempsey.
Though Washington later denied using the word backstage at the 2007 Golden Globes, Knight said he was inspired to come out publicly after hearing his co-star use the word. "I've never been called that to my face," he told Ellen Degeneres. "So I think when that happened, something shifted, and it became bigger than myself."
Washington was fired from the show shortly thereafter, but said he believed racism had been a factor in his dismissal, and claimed the Knight had manipulated the controversy.
Turns out Jerry wasn't having it after a 2010 incident in which a scantily-clad, beer-swilling "Mother Monster" was moved from her front row seat to his empty box after flipping off photographers.
"This woman is a jerk. I hate her," Seinfeld said during a WFAN radio interview. "I can't believe they put her in my box, which I paid for."
He went on to note, "You give people the finger and you get upgraded? Is that the world we're living in now?"
But his comments didn't end there. " You take one 'A' off of that and you've got 'Gag,'" he told the New York Post.
Kelly Osbourne and Christina Aguilera have been feuding for almost 10 years.
The drama reportedly started in November 2003 at the MTV European Video Music Awards when Aguilera allegedly said, "Oh Lord, I didn't realize it was still Halloween" as Osbourne took the stage.
Fast forward to this past October when Osbourne used her platform on E!'s "Fashion Police" to slam Aguilera. "She called me fat for years... I was never that fat," said Osbourne referring to Aguilera's appearance at the Michael Jackson Tribute Concert in Wales.
They may have played the best of friends onscreen, but Betty White revealed that long-standing rumors that she and co-star Bea Arthur were, in fact, true.
"Bea was not that fond of me," White told Joy Behar while promoting her memoir, "If You Ask Me (And of Course You Won't)" last year. "I don't know what I ever did but she was not that thrilled with me."
White spoke at more length about the feud to Entertainment Weekly, saying that Arthur wasn't fond of her positive attitude and was the primary reason a "Golden Girls" reunion had never materialized. "There were talks, but Bea wouldn't do it," she lamented.
Abercrombie & Fitch is renowned for its sexually-charged ads featuring hunky models in various stages of undress, so it might come as a surprise that the popular retailer asked "Jersey Shore" star Mike "The Situation" Sorrentino, who has never been shy about showing off his own toned abs, to stop wearing their clothes last summer.
"We are deeply concerned that Mr. Sorrentino's association with our brand could cause significant damage to our image," company officials said in a statement at the time. "We understand that the show is for entertainment purposes, but believe this association is contrary to the aspirational nature of our brand, and may be distressing to many of our fans."
Sorrentino filed a lawsuit several months later, claiming that Abercrombie had infringed on "Jersey Shore" trademarks like GTL and the Situation trademarks.
Things got nasty when two very different drag legends came together to at the 1993 MTV Video Music Awards.
RuPaul presented an award with Milton Berle after the two reportedly had an uncomfortable exchange backstage (Berle was allegedly sexually inappropriate and rude to the "Drag Race" host).
Once in front of the audience, a visibly agitated RuPaul went off the script and remarked to Berle, "So you used to wear gowns, but now you're wearing diapers."
Berle responded in kind with, "Oh, we're going to ad lib? I'll check my brain and we'll start even."
MTV.com calls the incident "one of the most uncomfortable moments in VMA history."
Their 1962 pairing history in "Whatever Happened to Baby Jane?" is truly cinematic legend -- but Bette Davis and Joan Crawford reportedly detested each other for over 30 years.
Davis once reportedly quipped of Crawford, "She slept with every male star at MGM, except Lassie."
But as a retort, Crawford is said to have sniffed of Davis, "She looks like she's never had a happy day, or night, in her life."
In May 2007, it was truly the political catfight heard round the world when O'Donnell sparred off against fellow "The View" co-host Hasselbeck, calling her "cowardly."
"You are my friend since September," O'Donnell told Hasselbeck. "Do you believe that I think our troops are terrorists? And you would not even look me in the face, Elisabeth, and say, 'No, Rosie.'"
Hasselbeck shot back: "You are an adult, and I'm not going to be the person for you to explain your thoughts. ... Defend your own insinuations."
O'Donnell eventually agreed to cut short her contract agreement with ABC as a result of the argument.
Hip hop has always had its fair share of feuding rappers, but things are particularly ugly between gay faves Nicki Minaj and Lil Kim.
The name and cover art for Kim's latest mix tape, "Black Friday," was directly inspired by Minaj's debut album, "Pink Friday," but with a gruesome twist -- the cover features Kim holding a bloody sword and what appears to be Minaj's dead body slumped in the background.
While Minaj has made several tracks that are rumored to be about Kim, in an interview with Angie Martinez she said that she still respects Kim and the work she's done. However, she isn't afraid to bring the beat down when necessary: "You know when a mom says, 'It hurts me more to beat you than it hurts you?' [Lashing out] doesn't take away the love that I have [for Kim]."
Few television series go on to achieve the international success of "Sex and the City," but Sandra Bernhard insists she has no regrets about turning down the chance to play one of the now-iconic characters.
In a new interview with Howard Stern, Bernhard revealed she was originally offered the role of Miranda Hobbes, but opted out due to the "terrible" original script and low paycheck.
Never one to mince words, the comedian also took the opportunity to diss the show's star Sarah Jessica Parker, who also served as executive producer. "I would have had to play third or fourth fiddle to Sarah Jessica Parker and put up with her s**t," she hissed. "It would have been hideous to work with her."
Perhaps it was meant as an homage, but Beyonce was harshly criticized for her "Countdown" video, which may believed ripped off the work of choreographer Anne Teresa De Keersmaeker.
De Keersmaeker was more diplomatic about the allegations, but nonetheless, her feelings were mixed at best. "People asked me if I'm angry or honored," she said. "Neither, on the one hand, I am glad that 'Rosas danst Rosas' (which she choreographed) can perhaps reach a mass audience which such a dance performance could never achieve, despite its popularity in the dance world since 1980s. On the other hand, there are protocols and consequences to such actions, and I can't imagine she and her team are not aware of it." was more diplomatic about the allegations
The legendary comedian and fashion commentator sounded off on the troubled "Mean Girls" actress in 2010. "Lindsay Lohan said she wouldn't mind being under oath because she thought Oath was a Norwegian ski instructor," Rivers cracked at one point. Another zinger: "I was reading about the Lindsay Lohan diet ... all liquid. 80 Proof."
After learning that Duff had been cast in a remake of "Bonnie and Clyde," Dunaway -- the star of the original film -- sniffed, "Couldn't they at least cast a real actress?" But before you think Dunaway's gone all "Mommie Dearest" on us yet again, Duff offered up some choice words, too.
It should come as no surprise that two of the most successful female pop singers had long had an adversarial relationship.
However, things came to a head in 1995, when the Material Girl reportedly told a journalist that Carey wasn't particularly bright.
But it's Mimi who eventually had the last laugh with a diss of her own.
Madonna wasn't the first to claim that Lady Gaga stole elements of her act: the Divine Miss M also sounded off on the Mother Monster earlier in 2011.
After Lady Gaga performed in a wheelchair in Australia, Midler slammed the pop star on Twitter. "
I'm not sure @LadyGaga knows that I've performed my mermaid in a wheelchair for millions of people -- and many of them are still alive," she tweeted.
She went on to note, "Dear @LadyGaga if you think a mermaid in a wheelchair seems familiar-it's because it is! You can see it on youtube 24/7-- with ME performing it ...
I've been doing singing mermaid in a wheelchair since 1980-You can keep the meat dress and the firecracker t*ts - mermaid's mine."
When Lambert appeared on the cover of "Out" magazine's 2009 Out 100 issue, Hicklin dedicated his entire Editor's Letter to addressing his beef with the pop star. It appears that Lambert's team had warned the magazine not make him appear "too gay," a term of their agreement that Hicklin found offensive.
The editor wrote: "You're a pioneer, an out gay pop idol at the start of his career. Someone has to be first, and we're all counting on you not to mess this up. You have to find your own path and then others can follow. We just hope it's a path that's honest and true and that you choose to surround yourself with people who celebrate your individuality. The irony is that right now it would be easier to get Kris Allen to do a solo cover shoot for us. But only because he's straight."
Lambert responded to Hicklin on Twitter saying, "Dear Aaron, it's def not that deep. Chill! Guess ya gotta get attention for the magazine. U too are at the mercy of the marketing machine."
And in an interview with Entertainment Weekly, Lambert said: "I think that the editor has his agenda and has his opinions, which I respect, but they're not necessarily my opinions. And I wish there was a little respect for that. Not every gay man is the same gay man... He really crossed a line."
However, in 2011 Lambert posed for the magazine again and buried the hatchet with Hicklin saying, "I have no hard feelings. That was then, and I've learned a lot."
It's difficult to imagine the woman who played Mary Poppins ever starting a Hollywood catfight -- but Julie Andrews got in a slight dig at Audrey Hepburn. Upon winning the Golden Globe for Best Actress, Andrews thanked Jack Warner, the studio tycoon who cast Hepburn as Eliza Doolittle in "My Fair Lady" rather than Andrews, who had originated the role on Broadway. Hepburn had been nominated in the same category.
Broadway's original Eva Peron has made it clear she doesn't want Argentina (as well as the rest of the world) to cry for her, but she wasn't too happy when Andrew Lloyd Webber dumped her in favor of Glenn Close for the New York premiere production of "Sunset Boulevard" in 1994.
LuPone, who eventually won a lawsuit against Lloyd Webber for her unceremonious dismissal from the show, has sounded off on Close on multiple occasions, most recently in her autobiography, published in 2010. She writes: "Do I think Glenn Close was complicit in what happened to me? ... What I do know is that from the time she was announced, I never heard from her."