After SPOILER happens, and Cameron Frye freaks out, Ferris drops a wee bit of RP I've never noticed til after hanging around here for a while:
"Cameron has never been in love; at least no-one has ever been in love with him. If things don't change for him, he's going to marry the first girl he lays.
And she's going to treat him like shit. Because she will have given him what he as built up in his mind as the be all and end all of human existence.
She won't respect him, because you can't respect someone who kisses your ass.
It just doesn't work"

Edit: Another blatant one; A young Charlie Sheen, in the police station, arrested/brought in for drugs. He's almost the picture of not giving a shit or trying to impress anyone, he just calls it like it is.
Dark Triad traits (almost classically stereotypical leather jacket thrown in), combined with calling a Jennifer Grey's character on her shit rather than letting it slide, and 5 minutes later she's playing tonsil hockey with a guy she just met.

TL;DR: Classic movie seeded with a few RP gems.