Like Disney, Marvel is known to hide Easter eggs in their films the same way Disney hides hidden Mickeys. But they usually come as quickly as they go and you’d have to be really alert to catch them all. The beauty of these Easter eggs is the element of surprise and the feeling of knowing the “inside joke” that the producers and directors of the films are sharing with you. Some require you to stay until after the movie for the post-credit scene.
There were even a few in the recently released, “Guardians of the Galaxy” but blink and you might’ve missed it.
Source: Marvel
MTV took the liberty of breaking down all the Easter eggs from 2008′s “Iron Man” through 2013′s “Thor: The Dark World” in a 13-minute montage. The video also explains the relevance of these Easter eggs and how it’s connected to things that only hardcore Marvel fans would understand i.e. references to stories and characters from years of comic books, films, TV shows, etc. However, there’s nothing about “Captain America: The Winter Soldier” or “Guardians of the Galaxy” in there.
Still worth watching though! Here:
And if you want to skip ahead to your favorite:
0:14 – “Iron Man”
2:03 – “The Incredible Hulk”
4:16 – “Iron Man 2″
5:42 – “Thor”
6:47 – “Captain America: The First Avenger”
8:09 – “The Avengers”
9:43 – “Iron Man 3″
10:50 – “Thor: The Dark World”
You’re welcome!
(Source)