When Fury tells Coulson about The Winter SoldierCoulson should be all like "YES!" and pull out a set of vintage Bucky Barnes trading cards << Coulson: The second happiest person to find out Bucky is alive.
The interactions between Thor and the other Avengers. Always puts a smile on my face. The next Avengers movie should definitely have a funny scene with this in it. XD I feel like Thor would call him metal man though.