When Sir Elton guest judged on Season Three of Idol, he proved his passion for the show and why he'd be a welcome fiesty addition to the judges' panel. After Jennifer Hudson was eliminated despite a strong performance, John spoke out, telling the press, "The three people I was really impressed with — and they just happened to be black, young female singers — all seem to be landing in the bottom three …I find it incredibly racist.? Bonus: he'd bring the British wit the show is losing with the departure of Simon Cowell.
Gene Simmons made his first Idol appearance during the auditions for Season Four, and returned to back Adam Lambert at the Season Eight finale. The Kiss bassist has a reality-tv rÃ©sumÃ© (his Family Jewels show on A&E), a big mouth with absolutely no filter and a four-decade career in the music biz — the perfect combination for an American Idol judge.
Katy Perry made a splash during her brief stint on the Idol judges panel for Season Nine auditions. Her ethos: ?I?ve always been a brutally honest type of gal? People are going to get the best advice that they need to hear.? She even threatened to toss a Coke in Kara DioGuardi's face. Sign this girl up, stat.
He's not the biggest star American Idol has ever produced, but he's the most controversial — and one of the most beloved. Lambert proved his judging mettle as a guest mentor on Season Nine, pulling no punches as he critiqued singers like Lee DeWyze (?Here, there's nothing going on," he said of Lee's face) and Andrew Garcia ("I was bored"). There's no doubt he'd bring a lot of sass and glam to the panel.
Quentin Tarantino is brash, hiarious, and clearly loves American Idol. He popped up as a guest judge on Season Three (when he told Diana DeGarmo "You pulled off the notes … but I don't care), then again on Season Eight, when Adam Lambert unfurled his screamy version of "Born to Be Wild." Idol could use his manic energy and enthusiasm on the panel next season.
Jennifer Lopez, the frontrunner to replace Ellen DeGeneres next season, has Paula Abdul's song-and-dance chops and reality-TV cred, too: she created the MTV series Dancelife and guest mentored on Season Six of Idol — yes, she gave advice to Sanjaya. Her verdict: "He really, really impressed me."
Idol can always use more rock & roll energy, and vet Slash is an extremely well-spoken and clever musician with an ear for both hard rock and pop (he features Fergie on his most recent solo album and contributed killer guitar work to Rihanna's "Rockstar 101"). His guest mentor stint on Season Eight ranks among the most fun and memorable in the show's history.
Season Five mentor Stevie Wonder is one of the greatest musicians to ever grace the Idol stage. The Rock and Roll Hall of Famer would bring four decades of knowledge and a whole lot of soul to the judges panel.
Stewart brought some cheeky fun to the Season Eight finale with his performance of "Maggie May," and served as a guest mentor on the show's fifth season, where he tangled with spitfire Kellie Pickler (she told him his advice "took a load off my chest") and cracked jokes about Ozzy Osbourne.
Idol rarely gets the chance to work with an original diva. Diana Ross joined the show to mentor on Season Six, which means yes, she too encountered Sanjaya (her verdict: "Sanjaya is love!"). Since Idol spawned an Oscar-winning star of Dreamgirls, it's only fitting that the original Dreamgirl herself put in some more time on Idol, right?
Cyrus proved herself to be a bright, fun and enthusiastic mentor when she joined the contestants on Idol's Season Nine. Bonus: she's the potential candidate who's closest in age to the hopefuls, making her uniquely positioned to offer advice on getting a young career off the ground.
Jamie Foxx took his mentoring gig on Idol so seriously during Season Nine, he had Lee DeWyze singing mere inches from his own face. This kind of up-close-and-personal style made great TV and showed why Foxx shines on camera: he's bold, brash and never afraid to speak his mind.
Mariah's history on the big and small screens is checkered — and the potential for Abdul-style wackiness should she join Idol would be off the charts. Fans could look forward to visits from her Jack Russell terrier, tangents about butterflies and notes to contestants about hitting the perfect whistle pitch.
It's been eight years since Twain released a studio album, but she proved why she's one of country's most charismatic stars on Season Nine of Idol as she guest judged during the auditions and mentored the Top Six.
Blige guest judged during Season Nine and sang "Stairway to Heaven" on Idol Gives Back, and nearly pulled Elliott Yamin's arm out of its socket during their duet on U2's "One" during the Season Five finale. "You have to find some humlity … and stop trying to exalt yourself" she told an overzealous hopeful during auditions. "I didn't know if he was gonna pull out a gun or what!" We could use more of that kind of drama in our Idol lives.
She proved she has an awesome sense of humor with her guest spot on Glee, and got in early on Idol, mentoring on Season Two. The legend would bring theatrics and spunkiness to the judges' panel (as well as an awesome accent).
He isn't a vocal superstar by trade, but Neil Patrick Harris proved he's got a strong voice during his stint hosting the Tony Awards. He's been on hit TV shows that span at least two generations, and is one of the wittiest guys in Hollywood. His wry commentary could combine the wit of Ellen DeGeneres with the bite of Simon Cowell.
With No Doubt wrapping up a new studio album, it's unlikely Gwen Stefani could find time to sit in on Idol every week. But the Season Six mentor would be great for the judges' mix: she's sweet, charming and an inspiration to young girls (Harajuku and otherwise) worldwide.
Nobody does it like Dolly: country's original spitfire is still going strong five decades into her remarkable career. Her live shows are as uproarious as a standup act, and her voice is as sharp as her wit. She's also a masterful orchestrator and arranger, turning out fascinating cover songs on many of her recent discs. Her commentary as an Idol judge would be loud, proud and hilarious.
Ever since he told David Cook to imagine he was singing to an underage chorus girl during Season Seven, the Broadway legend has been an unlikely Idol favorite. He's as British as Simon Cowell but as wacky as Paula Abdul: a winning combination.