I'll Be Your Best Friend

Okay, Alice is trying to get some MacGuffin from Bob, but Bob doesn't want to give it up for free. Alice really doesn't have anything of value to offer, but she doesn't want to just let Bob walk away with the MacGuffin. In desperation, she says "I'll be your best friend!" This Stock Phrase is the staple of every character who fails at negotiation.

Film
"Alyssa: If you come and pick me up, I'll be your best friend."
 * Chasing Amy

"Zoe: [to Kim] I'll be your best friend! [makes several other offers before reaching a deal]"
 * Death Proof


 * In a negative fashion, Tom Hanks, in The Money Pit extracts a loan from the 12 year old, super rich, rock star by telling him, "If you don't loan this money, I won't be your friend any more!" He got the loan.

Literature

 * The Pigeon tries this in the children's book Don't Let The Pigeon Drive The Bus.

Video Games

 * Used in Golden Sun 2 by the first Djinni you meet, if you keep refusing to take him along with you. He comes along anyway.
 * Guybrush uses it at one point while asking repeatedly a pirate for a bucket in Monkey Island 2: LeChuck's Revenge.
 * And in Tales of Monkey Island Elaine says it to Guybrush when convincing him to help LeChuck in the quest for the Summoning Artifacts, spoofed as Elaine is Guybrush's wife.

Western Animation
"Mung Daal: We're not open yet. Birdman: Aw come on, let me look. I'll be your best friend!"
 * Chowder episode "The Garage Sale"

"Zorak: Moltar, take off your helmet... show me your true face. Moltar: No. Zorak: C'mon... I'll be your friend."
 * Space Ghost Coast to Coast

"Man: Now don't you fret. When I'm through, he won't set foot in this town again. I can be very, very persuasive. reloads his gun [Scene change to a bar] Man: whining C'mon, leave town! Bob: No. Man: I'll be your friend? Bob: No. Man: Aw, you're mean!"
 * The Simpsons has this exchange when Homer hired a guy to chase Sideshow Bob out of Town:


 * One Butterfinger ad had Milhouse use this to try and get Bart to share his candy bar. Bart's response: "You already are."