Hope your stocking can handle lots of coal, because this shot of Jake Gyllenhaal as a marine in 2005's Jarhead spawns very, very naughty thoughts!
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CAN YOU BARE IT?
We'd talk about how cute his swim trunks are in this 2009 photo from Martha's Vineyard, but face it – you're not looking at his shorts.
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The actor simmers in a (fully clothed, sorry) side-view shot from 2005.
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If your heart didn't melt at this 2004 shot of Gyllenhaal cuddling an adorable dog, then you have no soul. (Thanks for reading PEOPLE.com, Voldemort!)
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Casual's cool, but Gyllenhaal cleans up in traditional black tie at the 2006 Screen Actors Guild Awards.
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The surfer boy gets things wet during a beachy day out in 2005.
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Even in a low-key getup like a T-shirt and jeans, Jake looks like a million bucks.
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Behind door No. 3? A prize worth waiting for!
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Gyllenhaal's most devoted fans will recall falling for him in 2001's cult hit Donnie Darko, where he played a disturbed teen (aww, emo eyes!) who has visions of a bunny that tells him when the world will end. Really.
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Skipping a necktie and a shave, Gyllenhaal heats up the press line in October.
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RIDE 'EM, COWBOY!
He scored an Oscar nod for his turn as Jack Twist, a cowboy in love with another man (played by Heath Ledger) in 2005's Brokeback Mountain. Say it with us: "I wish I knew how to quit you."
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He's the most wanted man, premiering The Prince of Persia: The Sands of Time in L.A. in May.
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The actor takes his biceps for a jog, sunning those guns in L.A. last August.
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HEAD OF THE CLASS
Ari Gold or Jake Gyllenhaal? The actor channels the suave Entourage character this past May in New York. Yes, let's hug it out. Several times.
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CHEST IN SHOW
Gyllenhaal took it off – and kept it off – for this year's action pic The Prince of Persia: The Sands of Time.
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He's more than just a pretty face! The charitable actor plants himself in the middle of a photo, taking part in the Green Service Day project at an L.A. high school.
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After a string of well-received indie films, Gyllenhaal – and an incredibly thick head of hair – make an action film debut in 2004's Day After Tomorrow.
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Crisp in a snow-white henley, Gyllenhaal shows off his new flick, Love and Other Drugs, in October.
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Gyllenhaal gets tongues wagging – literally – hanging out with his puppy friend in 2006.
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A SERIOUS MAN
The actor strikes a serious pose during a 2005 Jarhead press conference.
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Get your swerve on! The star embraced his inner sk8er boi while weaving around New York City traffic in 2006.
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At 19, an adorably fresh-faced Gyllenhaal landed his first lead role in October Sky, a 1999 film about a NASA scientist's rocky upbringing.
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He may not have taken home the Oscar at the 2006 Academy Awards, but Gyllenhaal was a winner on the red carpet.
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Time for more cardio – although the way your heart may be pounding after looking at all these shots of Jake, you could probably skip the gym.
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We'll go for the obvious joke: Gyllenhaal got lei'd in Hawaii in 2005.
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LEAN INTO IT
In 2005, Jake still had a boyish look to him while promoting Jarhead.
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With a shorn hairdo and traditional bowtie, Gyllenhaal makes the scene at the 2010 Academy Awards.
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Another shirtless photo of the birthday boy. C'mon, it's not like you're complaining.
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No wonder Anne Hathaway falls for him in Love and Other Drugs – just check out that smile (and those forearms)!
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THE FINAL SHOT
Gyllenhaal heats up Cannes in 2007. Happy birthday, Jake!