Tony's response for being called as "Da Vinci of our time"?
"Absolutely ridiculous. I don't paint."
Tony at the beginning.
"I don't want to see this on your MySpace Page. Please, no gang signs... No, throw it up, I'm kidding."
"Yeah peace, I love peace! I'd be out of a job with peace..."
Also at the beginning:
Soldier: Is it true that you went twelve-for-twelve with the Maxim Girls last year?
Tony Stark: That is an excellent question. Yes and no. March and I had a scheduling conflict but fortunately the Christmas cover was twins.
Also also at the beginning:
Tony: I'm sorry, this is the fun-vee. The hum-drum-vee is over there.
And then after Tony is kidnapped and assumed dead, he is reunited with Rhodey, who finds him haggard, injured and near complete exhaustion:
Rhodey: How was the fun-vee?
During Tony's escape from the Afghanistan caves, he gets his gauntlet jammed in a rock face when trying to take out a soldier. Another one sees an opportunity for a Boom, Headshot. He walks right up beside Tony for point blank aiming and... The bullet ricochets off Tony's helmet, and into the headof the shooter.
A brief moment during the final fight scene. Tony's just started getting out of his suit, thinking that he's won and he can take it off, when Iron Monger appears behind him. He turns and lifts his hand to deliver a repulsor blast... Only to find that he's already taken the armored glove off of it and his hand is bare. He actually turns his palm to stare incredulously at it for a second before getting slammed in the face.
"TONY STARK WAS ABLE TO BUILD THIS IN A CAVE! WITH A BOX OF SCRAPS!" "Well I'm sorry... but I'm not Tony Stark."
The little exchange between Coulson and Pepper while they infiltrate Sector 16.
Pepper: Oh what is that, some kind of device to pick the lock?
Coulson: You might want to step back...
Pepper then turns around and covers her ears in expectation of a huge bang, only for the lock to blow in a small "poof."
A dying Tony has just failed to grab the prototype Arc Reactor that Pepper saved and had monogrammed, and is lying there, beaten... until Dummy casually lowers it into frame. Doubles as a CMOH.
Tony: Good boy...
The scene where Pepper swaps out Tony's Arc Reactor for the upgraded model. Particularly this line: