In Captain America, as Cap engages in his morale boosting tour to entertain the troops, the audience are treated to a set-up of one of the most famous Captain America moments, when the hero took down Hitler with a well-placed punch to the chops. That in itself is of course an Easter Egg, as it pays homage to the cover of Captain America Comics #1 from 1941, but the Avengers takes the Easter Egg a little further. After Coulson's death, Nick Fury uses his collector cards to inspire the Avengers to action, and when he tosses the bloodied cards onto the desk we get a brief glimpses of one of the cards, which is a recreation of that same cover, featuring the same Fuhrer punch.