Let's all be adults; this is not a puerile discussion of the male member. We're merely noting that throughout history, while paintings and sculptures have depicted the nude male body with regularity, film has a limited number of offerings (not counting the XXX variety, of course), whereas leading ladies (even Oscar-winning ones) drop cover again and again.

Michael Fassbender, however, has no qualms about showing what God gave him. In Steve McQueen's new drama "Shame," Fassbender plays a sex addict who's in the buff so often his body is naked nearly as often as its clothed. In honor of Fassbender's courage to reveal everything, we're celebrating the movies -- and actors -- who've dared to go full frontal.

9. 'A Very Harold & Kumar 3D Christmas' (2011)

In the stoner duo's take on holiday flicks, Harold (John Cho) and Kumar (Kal Penn) pay tribute to the infamous tongue-on-the-flagpole scene in "A Christmas Story," except the guys have been tied naked to a warehouse pole by Ukrainian mobsters. When Harold and Kumar try to escape, it's Harold's penis, not his tongue, that gets frozen to the metal. For the record, no penises were harmed for the scene; it was a prosthetic.

8. Harvey Keitel (Various)

There were many Keitel penis moments to choose from, so we're highlighting him rather than his movies. Keitel's family jewels memorably graced "The Piano," "Bad Lieutenant" and "Ulysses' Gaze" to name just three of his full frontal films. The actor is so renowned for displaying himself on camera that comedian Dennis Miller regularly included the joke "I've seen Harvey Keitel's dick more than I've seen my own ... and I look at mine a lot!" in his stand up.

7. 'There's Something About Mary'(1998)

Not all penis scenes are created equal, and few are as funny as Ben Stiller's scene-stealing "Frank and Beans," which get stuck in poor young Ted's zipper the evening of his prom -- at his dream date's house. It's impossible to decide what's most unforgettable: the look of agony on Ted's face, the gut-busting reaction by Mary's family (particularly stepfather Keith David), or the image of the injured penis -- oh the horror!

Also Check Out: 'Members Only With Michael Fassbender on MTV.com

6. 'Watchmen' (2009)

Strictly speaking, we'll never know how much of Dr. Manhattan's computer-generated blue body is true to actor Billy Crudup's own physique, but it doesn't really matter -- the perfectly sculpted Watchman is quite memorable.

Instead of glossing over the energy-based superhero's manly parts (the way Mystique's bod remains relatively modest in "X-Men"), the blue being's bold penis is on full display again and again.

5. 'Boogie Nights' (1997)

The entire movie is based on the premise that Mark Wahlberg's Dirk Diggler has the one prodigious talent necessary for a successful career in the porn industry, but his tool of the trade is never shown ... until the final scene of the movie. And after two hours of wondering and imagining, there it is in all its prosthetic foot-long wonder. But like the has-been Diggler, the big reveal at that point is as sad as it is startling.

4. 'Wild Things' (1998)

There are plenty of memorably steamy scenes in this sex-filled drama (male viewers may fondly recall the menage-a-trois featuring Neve Campbell and Denise Richards), but the one "Did that really happen?" moment is an unexpectedly candid shot of Kevin Bacon in the shower. He's talking to Matt Dillon while holding a towel across his chest -- but not his privates. It's a scene that adds a whole new dimension to the Six Degrees of Kevin Bacon game.

3. 'Forgetting Sarah Marshall' (2008)

Jason Segel drops his towel in an early scene of the comedy he co-wrote and produced. The penis shot, naturally, is played for laughs. There's 6-foot-4 Segel completely naked and crying like a baby during one of the most simultaneously cringe-worthy and hilarious break-up scenes ever. Segel all wet and distraught isn't just funny, it's a genius reminder of how nakedly raw and exposed being dumped can feel.

Also Check Out: Michael Fassbender Likes Sex (a Lot) in 3 'Shame' Clips

2. 'The Crying Game' (1992)

There's no other penis moment in film history that has caused as many gasps -- as any unspoiled viewer of Neil Jordan's Oscar-winning Irish drama can attest. We'd say SPOILER ALERT, but the twist is a pretty pervasive cultural reference. The scene when the beautiful Dil (Jaye Davidson) disrobes midway through the story, and the camera lingers on the hitherto female character's manhood, is brilliant and shocking and unforgettable.

1. Any Ewan McGregor Movie

No other Hollywood actor (again, excepting those who qualify for AVN Awards) is as much at ease with nudity as the handsome Scotsman. Scarcely a drama in his resume doesn't include a shot of him in all his glory. There's "Trainspotting," "The Pillow Book," "Velvet Goldmine," "Young Adam"… pretty much anything bearing his name and an R rating. We hereby dub McGregor the king of the cinematic full monty.