A few lines I won't miss if I never have to hear them again in a movie or read them in a novel:
"All right, I admit I was there that night! But I didn't kill him/her! He/she was already dead!"
"I'd never hurt him/her! I love him/her!"
"Say, how many years have we known each other now?"
"I had the strangest dream last night!" (Followed by long description of dream.)
"Do you remember the time....?" (Followed by recounting of childhood incident designed to fill in back story but actually taking us totally out of the flow of the story).
"I've let you down...you and the kids. But I swear I'll make it up to you."
"It's not what it looks like!"
Feel free to nominate some of your own in the comments!