Perhaps one of the reasons directors love him is Fassbender's unwavering dedication to his craft.
He's been known to read a script 300 times before filming (though we can't imagine he read 300 that many times, that would just be silly). Fassy's pretty certain where his diligent work ethic comes from, too, attributing it to his German father, Josef.
"If I came home with 85% in a test, he'd always ask what happened to the other 15%."
"I always approach film as a fan," Fassy's said.
Unlike some actors who value stage work more than their dabblings at the cineplexes, Fassbender's a movie man through and through.
"In drama school, they don't think of movies as a pure form like theatre, and it's films that I love most," he's said of his time studying at London's Drama Centre. "There's an intimacy in movies - I wanted to have the same impact on others that movies had on me."
It's not hard to see why Fassbender loves the movie so much when he has people like Quentin Tarantino as his celluloid heroes. Michael worked with Tarantino on Inglourious Basterds , where the auteur's passion for pictures proved infectious.
"You know the man eats, breathes, lives film," Fassbender says. "You could bring up the most obscure movie, like some fuckin' Swedish film from 1963 or whatever, and he'll know it. It's quite staggering, actually, he is encyclopedia of knowledge."
And how about acting heroes? "For me, Daniel Day-Lewis is in a league of his own. I think that he's amazing. And he's always been a benchmark of excellence." Yep, doesn't get much better than that.
Though he's wearied recently over incessant chatter about his full-frontal moment in Shame , Fassbender stands by the work. "It was important to go all out, not take shortcuts there, and to be sort of naked in every respect," he says. "Otherwise, I don't think the film would have worked."
He was also all up for addressing the gender imbalance when it comes to on-screen flesh-bearing.
"To be honest with you, I think it's the idea of male frontal nudity," he says of just why his pant-less promenade has garnered so much attention. "It just baffles me: women can parade around naked all the time, but the guy conveniently has his pants on.
"I remember my mum always complaining about that to me, saying, 'This is such bullshit, it's always the women who are naked' ... So I did this one for you, Mum!"
Before he dropped his trews for Shame and went all-out nasty in 12 Years A Slave , Fassbender made audiences sit up with his affecting turn as bastard Connor in Brit flick Fish Tank.
Fassbender remains pragmatic about leaving characters on set when he's finished shooting, though. "It washes away," he says. "I think it's important to go to places that are uncomfortable. For the benefit of others, maybe.
"You're facing all these ugly things, and knowing well this is an ugly thing and it's there somewhere in all of us. And so you're representing the ugliness.
"Connor does cross the line in Fish Tank , but on the flip-side he is the catalyst for [ the heroine ] to become her own person... And so it's again playing with that ambiguity."
Where Fassbender's concerned, the scarier the better - at least when it comes to taking risks in the acting biz.
"The problem is, we feel a lot of pressure about looking silly or appearing weak, whatever that means, or being a failure," he says. "You have to keep in your head: what's the worst that can happen? I'm trying to tell a story - what's the worst that can happen? You fall flat on your face, then hopefully you get back up again and go for it again and try something else.
"We're all going to die one day. I'm stealing that off Steve [ McQueen ]; it's what he'd say when he ordered me to take my clothes off. 'WE'RE ALL GOING TO DIE ONE DAY!'" Too right.
He's not above admitting that his Haywire co-star, Gina Carano, could easily kick his ass off-screen. "In real life, Gina would beat the shit out of me in any circumstance. I mean, have you seen her on YouTube?" he laughs.
Not that Carano went easy on him during filming. During their showstopping hotel brawl, Carano was actually meant to miss Fassbender when she threw the vase. Instead, she got so caught up in the moment that she smashed the vase over Fassbender's head. What were we just saying about risks?
Like all the best people in the world, Fassbender counts himself as a Star Wars fan. Not only that, but when he was a kid, he had his very own Ewok village.
" Star Wars was really the only sci-fi sort of fascination I had as a youngster," he says. "I collected and I've still got the AT-AT and the Millennium Falcon and the Ewok village."
Going by his ability to describe the Ewok village pretty clearly, it seems he's still playing with it. "It's three trees or four, perhaps, joined together with a platform bit, it's kind of cool: you go into the trunk of one and come out of another, there are some winding trap things..."
Fassbender once staged his own stage version of Reservoir Dogs . He was 18 when he directed and starred (as Mr Pink) in the play, which he staged in his hometown of Killarney.
"It was pure naïveté and enthusiasm but a good lesson to learn by doing," he recalls. "I basically didn't know what I was getting myself into and there were plenty of hitches."
Oh, and did we mention he staged the show in order to raise money for charity? "We also had problems finding a charity that would take our money - nobody wanted to be associated with Reservoir Dogs . It's funny that nobody wanted our money…"
Years later, when he met with Tarantino to discuss playing a character in Inglourious Basterds , Fassbender was actually interested in tackling Nazi baddie Colonel Hans Landa (a role eventually taken by Christoph Waltz).
"I had sort of done 27 hours of prep on that, and then I arrived and Quentin said, 'Okay, let’s take a look at Hicox.' And I thought, shit. 'What about Landa?' And he said, 'Oh, I cast my Landa on Tuesday.'
"So I just did a cold reading of Hicox and although they had said to prepare Hicox as well, I didn’t have time to mediate between the two. But they seemed to like it."
Enough to give Fassbender the role when Simon Pegg, who was originally set to play Hicox, pulled out because of a conflict in his schedules.