I'm not one for lists usually, but I have to add two submissions to Filmcritic.com's Top 50 Movie Endings of All Time. First, since they're surprisingly light on horror films, I'd add John Carpenter's Halloween. Between the disappearance of Michael Myers, the look on Jamie Lee Curtis' face, and the legendarily creepy music you know in your gut that "You can't kill The Boogie Man." Plus, he's outside the theater somewhere waiting for you, maybe in your own house.
Second, a quintessential guy movie, Ocean's Eleven, has a quintessential bit of guy humor when George Clooney, as Daniel Ocean, is met by Brad Pitt's Rusty Ryan when Ocean gets out of prison wearing the tuxedo from the night he got busted in Vegas:
Rusty: I hope you were the groom.
Ocean (after a slight pause): Ted Nugent called. He wants his shirt back.
Not to mention the circularity of this scene as it ties to the beginning of the movie.
Bonus bantering
Tess Ocean: We need to get Rusty a girlfriend
Rusty: There's a women's prison just up the road
And further in the comedy vein, the end of Young Frankenstein is to die for. Madeline Kahn as The Bride followed up by Teri Garr asking "But what did you get from The Monster?" just leaves you howling.
Must... stop... thinking... about... this!