Well, it is my favorite line in the movie, and, in my opinion, one of the funniest lines ever written for a comedy (at least, a sex comedy).
"Fighting for peace is like screwing for virginity." - George Carlin

I would have assumed that everybody's favorite line of the movie was when the girl says, "Talk dirty to me" to the guy, and the guy's lineI won't even try to quote his dirty talk, but it just might be the single funniest line to come out of any Canadian movie.

Happy Birthday, Baby!

"Do you want to talk about how often I don't go down on you, or do you want me to go down on you?!"
Women eh?

My favorite was when the two friends are preparing to become "friends with benefits," and as they are getting prepared by drinking, the woman gives him a little speech on why and how they are going to do it (I'm going by faulty memory here) and then concludes with something like, "Now go ahead and finish your shot and after that your good friend [whatever the character's name was] is going to blow you."
I'm a single male, and I'm recommending this film to my female friend so that they will be similarly inspired.

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