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Everybody in This Is the End
This Is the End (2013)
Director/writers Seth Rogen and Evan Goldberg called in a lot of favors for their apocalyptic raunchfest. Though Michael Cera skews farthest from his real-world persona, there's plenty of comedy fodder among the self-styled performances of Rogen, James Franco, Jonah Hill, Jay Baruchel, Danny McBride, Craig Robinson, Emma Watson, Mindy Kaling, David Krumholtz, Christopher Mintz-Plasse, Rihanna, Martin Starr, Paul Rudd, Kevin Hart, Aziz Ansari, and Channing Tatum.
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High Fidelity (2000)
Though the Boss's cameo had its roots in Nick Hornby's original novel, High Fidelity's screenwriters wrote into their script with ulterior motives: they thought it'd get studios excited about the movie. Luckily, star John Cusack happened to be a Springsteen acquaintance, which helped the quickie scene become a reality — and gave Bruuuuuce a chance to prove that he's skilled enough to strum the blues and dole out romantic advice at the same time.
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30 Rock (2008)
If Liz Lemon (Tina Fey) is to be believed, Oprah in real life is just as nurturing and wise as she appears to be on TV. And sure, the writer's chance encounter with her idol turned out to be nothing but a drug-induced hallucination — but the woman herself was winning as Lemon's imagined version of Oprah (a.k.a. ''Borpo''), especially while delivering lines that revealed Liz had actually been interacting with a tweenage girl (''I lost my headgear at Six Flags! My boyfriend's in ninth grade!'').
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The Tinseltown series featured a slew of celebrities playing themselves from Eminem and Jessica Alba to Bob Saget and Mike Tyson, but it was only right that the show's executive producer made a record five cameos on the very show he inspired.
Written by Lanford Beard, Marc Bernardin, Hillary Busis, Simon Vozick-Levinson, and Kate Ward
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Britney acting? Not generally a great idea, though we'll always have a soft spot for Crossroads. Britney donning a sexy cheerleader outfit, a sexy teacher's ensemble, and a sexy white Madonna-inspired look to play herself as a figment of the Glee kids' imaginations — one with barely any lines? Much more successful, though we'll always think her suggestion to put ranch dressing on pizza sounds kind of gross.
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200 Cigarettes (1999)
The London-born troubadour was referenced throughout the New Year's 1981-set ensemble comedy — particularly in the scenes of high-strung party hostess Monica (Martha Plimpton), who worked herself into such a frenzy fearing no one would attend her party that she passed out before the ''Alison'' singer actually made an appearance. As we saw in morning-after montage, her loss was snarky feminist Ellie's (Janeane Garofalo) gain.
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There's Something About Mary (1998)
Cameron Diaz's dream girl had no shortage of suitors. But the only real knight in shining armor among them was Fav?ruh, a stand-up guy who was still in his Packers prime. His line readings were a little stilted, but his heart was pure — and with arms like that, who needs screen presence?
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Lauren Bacall and Ben Kingsley
The Sopranos (2006)
Sir Ben provided a hilariously blasé foil for Christopher (Michael Imperioli) when the mob underling headed down to Miami in hopes of ramping up his screenwriting career. No surprise, the Oscar winner was unimpressed by Christapha's pitiful film à clef Cleaver, but he did access some pretty sweet swag. Unfortunately for Bacall — also cameo-ing as herself — so did she, and the mobster sent a goon to mug her for the goods.
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MARIO LOPEZ AND PAUL KRUGMAN
Get Him to the Greek (2010)
ET's Mario Lopez gets laughs as one of the many real-life celebs who cross paths with fictional rock tool Aldous Snow (Russell Brand). But this comedy's funniest cameo player isn't from Hollywood at all — it's noted economist and New York Times columnist Paul Krugman, who shares a few supremely awkward moments with record-biz drone Aaron Green (Jonah Hill) in a TV greenroom. If he ever tires of writing Pulitzer-winning political analysis, we hope Krugman considers a new career in stand-up. —Hillary Busis
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JEAN-CLAUDE VAN DAMME JCVD (2008)
The Muscles from Brussels shows that he's more than a pretty face and a wicked kick in this drama, which has Van Damme playing an ex-action hero with financial woes who gets mixed up in a bank heist. Who'd have thought that the word pathos would ever be legitimately used to describe a Van Damme performance? —Hillary Busis
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NEIL PATRICK HARRIS Harold and Kumar Go To White Castle (2004) and Harold and Kumar Escape From Guantanamo Bay (2008)
The actor once commonly known as Doogie wasn't shy about shredding his wholesome reputation in this stoner comedy — Harris got high on Ecstasy, humped a seat, and stole a car as a stripper-loving version of himself. And as for what he does in the sequel, some things are best left as a surprise to unsuspecting viewers. —Kate Ward
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PATRICK STEWART Extras (2005-07)
Stewart was so good playing himself in Ricky Gervais' BBC/HBO comedy, he earned an Emmy nomination for Outstanding Guest Actor in a Comedy Series. He lost the award to Will & Grace's Leslie Jordan, but maybe he'll have better luck with that bawdy X-Men-lite script he told Gervais' Andy all about (''I'm walking along, and I see this beautiful girl, and I think I'd like to see her naked, and so all her clothes fall off''). —Kate Ward
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RYAN SEACREST Knocked Up (2007)
The affable American Idol host-turned-Crest spokesman veiled his pearly whites while unleashing a two-minute profanity-laced rant against young Hollywood after being told Jessica Simpson would arrive late to their scheduled E! interview: ''It doesn't make any sense. I got four jobs — hell, I'm more famous than half the people we talk to anyway!'' Hmmm... after this cameo, we're wondering if he could add ''comedian'' onto that rapidly expanding job title. (Second thought, after seeing his attempts at ''standup'' at the Emmy Awards, let's not.) —Kate Ward
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LARRY DAVID Curb Your Enthusiasm (2000-07)
David may have inspired Seinfeld's George Costanza, but the comedian took center stage in his own HBO sitcom as a neurotic, awkward Larry David who might as well glue his foot in his mouth. Though David's the bane of everyone's existence in Curb-land, we think he's pretty good. Pret-ty, pret-ty good. —Kate Ward
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Arrested Development (2003-06)
Fox's dearly departed cult series was home to a slew of memorable cameos — Judge Reinhold, Dave Attell, Andy Richter, etc. — but the Rocky star made a lasting impression on us, as well as on admirer Lucille 2 (Liza Minnelli), as Tobias' Burger King-loving, free-loading acting coach. —Kate Ward
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GARY BUSEY Entourage (2004-present)
Before he was kissing Jennifer Garner's neck at the Oscars, Busey was scaring the bejesus out of Vincent's gang after Turtle accidentally broke a sculpture crafted by the wacky, surprisingly Zen actor.
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PAMELA ANDERSON Borat (2006)
Sacha Baron Cohen's Borat literally tried to bag the Baywatch babe as his wife (Anderson, meanwhile, lost a husband — her marriage to Kid Rock ended only weeks after he reportedly blew into a rage after seeing the film). We'd say Borat had questionable taste, but then again, we're assuming Barb Wire never made it to Kazakhstan.
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DAVID DUCHOVNY The Larry Sanders Show (1992-98)
Larry Sanders found an unlikely admirer in Duchovny, who tried to woo his man-crush with an invite to a beach house and a Basic Instinct-esque peep show.
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JOHN MALKOVICH Being John Malkovich (1999)
The trippy Spike Jonze film takes Craig Schwartz (John Cusack) and others inside the mind of John Horatio Malkovich — not to be confused, of course, with John Gavin Malkovich, the actor's real name and identity. (Confused yet?)
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BOB BARKER Happy Gilmore (1996)
The Price is Right host sparred with Happy (Adam Sandler), his charity golf partner, and capped their violent showdown (heh!) with the brilliant phrase, ''Now you've had enough... bitch.'' See what could happen if you don't get your pets spayed and neutered?
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STAN LEE Mallrats (1995)
Comic book legends may be nerds, but it doesn't mean they don't get lucky in the romance department — Lee cited his ''running tally'' with rocker Mick Jagger while imparting some romantic advice to Brodie (Jason Lee) in Kevin Smith's sophomore film. (Lee, apparently, was in the lead).
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TOPHER GRACE Ocean's Eleven (2001) and Ocean's Twelve (2004)
Though Grace's guest appearance in the first buddy-heist flick got some chuckles, it was his cameo in the film's sequel — where the actor went ''all Frankie Muniz'' on Rusty (Brad Pitt) after trashing his hotel room — that really scored. And bonus points for that Kabbalah joke.
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BILLY IDOL The Wedding Singer (1998)
Who knew the hard-edged, '80s punk rocker was such a hopeless romantic? In the 1998 comedy, Idol helped Robbie (Adam Sandler) woo love interest Julia (Drew Barrymore) while on a flight to Las Vegas.
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MARCEL MARCEAU Silent Movie (1976)
The legendary mime famously spoke the only word — ''Non!'' — in Mel Brooks' speechless comedy.
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KURT VONNEGUT Back to School (1986)
When Rodney Dangerfield's rich businessman Thornton Melon was assigned a paper on Kurt Vonnegut's novels, he paid the Slaughterhouse Five author himself to draft the piece. Too bad his efforts were in vain — Vonnegut's paper earned Melon an F, and the following chastisement from his professor: ''Whoever did write this doesn't know the first thing about Kurt Vonnegut.''
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MARSHALL McLUHAN Annie Hall (1977)
The scholar and pop culture theorist helps Alvy Singer (Woody Allen) settle an argument — and break the fourth wall — while Alvy waits in line ahead of a pontificating know-it-all.
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BEN AFFLECK, MATT DAMON, AND GUS VAN SANT Jay and Silent Bob Strike Back (2001)
Affleck and Damon revisit their humble beginnings in the Kevin Smith-helmed comedy, filming the ill-advised Good Will Hunting 2: Hunting Season with Van Sant once again sitting in the director's chair. We're not sure that ''Applesauce... bitch,'' will catch on quite as quickly as the first film's pomme-related quip.
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CHER Stuck on You (2003)
In the Farrelly Brothers comedy, Cher pulls a Demi and hooks up with a much younger man (boy), played by Frankie Muniz.
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AL GORE 30 Rock (2006-present)
The former vice president took time out from saving the world to make a blink-and-you-missed-it appearance on the Tina Fey-helmed show. Too bad that whale was in trouble — we would've liked him to stick around.
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GEORGE MICHAEL Eli Stone (2008-present)
He's giving fame one more try: Michael's troubled star got a boost from his cameo in the feel-good ABC comedy, playing the subject of Stone's brain tumor-induced visions. (Prior to Eli Stone, Michael also guest starred as himself in Extras' finale).
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DAVY JONES The Brady Bunch (1969-74)
The Monkees heartthrob not only agreed to play at Marcia's junior prom, but he also offered himself up as her date. Hmm... think he'd ever heard of those statutory laws?
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MARISA TOMEI Seinfeld (1990-98)
Tomei may have dated Robert Downey Jr. in the '90s, but according to Seinfeld, the Oscar-winning actress really has a thing for short, stocky bald men — short, stocky, duplicitous bald men, however, don't make the cut (sorry, George!).
Written by Kate Ward, Simon Vozick-Levinson, and Marc Bernardin