Trivia: The directors have previously worked on both Community and Arrested Development - both shows get nods in this movie. Jim Rash, the Dean from Community, plays an MIT faculty member at the start. More subtle is the Bluth family's stair-car from Arrested Development, seen briefly as Captain America walks onto the airport runway before the big battle with the other Avengers.
Trivia: The sorcerors' WiFi password, Shamballa, is a reference to the 1986 Doctor Strange graphic novel "Into Shamballa."
Trivia: Doctor Strange casts a spell on the pizza vendor, played by Bruce Campbell, that forces him to repeatedly hit himself. This is similar to a scene from Evil Dead II, which sees Ash, also played by Bruce Campbell, attacked by his own possessed hand.
Trivia: The "wolf woman" seen in the montage at the start is played by Chris Hemsworth's wife Elsa Pataky.
Trivia: Stan Lee makes his usual cameo, this time as a patient at the asylum where Selvig is being held.
Trivia: While Bill Foster, played by Laurence Fishburne, is teaching the class, the words "Matrix" can be seen on the blackboard behind him, referring to the film series Laurence Fishburne starred in.
Trivia: Winston Duke's line "you bald-headed demon" was improvised.
Trivia: When Yelena is talking about Alexei wanting to relive his glory days as the Red Guardian, she sarcastically calls him Crimson Dynamo. In the comics, Crimson Dynamo is one of Iron Man's enemies. Ivan Vanko from Iron Man 2 was partly based on this character.
Trivia: After the ending credits role, stay tuned for a scene extra with Bruce Banner and Captain Marvel as they try to decipher the origin of the homing beacon the 10 rings are giving off.
Trivia: The tiny pizza being embiggened by Hank is a deliberate nod by Peyton Reed to Back to the Future Part II, where a similar thing happens. Reed directed some behind the scenes footage for that film very early in his career.