Trivia: Not sure if it was done on purpose, but when Tony and Happy are sparring and "Natalie" (Natasha) walks in, the song playing is "Magnificent Seven" by The Clash. It just so happens the Avengers (or the Avengers Initiative) are made up of Iron Man, Black Widow, Hulk, Thor, Captain America,, Hawkeye, and Black Panther.
Trivia: During the film's climax, a young boy in an Iron Man mask is shown standing up to one of the Hammer drones with Iron Man swooping in and destroying the drone and giving the kid the credit. Following Spider-Man's inclusion in the Marvel Cinematic Universe, a fan theory suggested the young boy was Peter Parker, which Marvel Studios President Kevin Feige and Spider-Man actor Tom Holland would later retroactively confirm.
Trivia: Near the end, where Nick Fury and Tony Stark are talking about the Avengers, there is a world map behind them featuring dots. The dots show where the Avengers are: New York (Iron Man); Arctic Circle (Captain America); Europe (Black Widow); Lower Africa (Wakanda for Black Panther); California (Hulk); New Mexico (Thor); Southern Atlantic Ocean (Namor the Sub-Mariner). (01:55:55)
Trivia: Spoiler: The film closely resembles several key Iron Man stories from the comics. The part when he was drunk references the "Demon in a bottle" storyline, where Rhodey dons an Iron Man suit. The part of him dying is somewhat similar to "Ultimate Iron Man." Also, the idea that his technology is used in a way he doesn't like and having a battle is similar to the "Armor Wars" plot.
Trivia: Attack of the Show host Olivia Munn mentioned she was to have another role in the movie. She played reporter Chess Roberts, but originally had a somewhat bigger role. She was to play a girl at Stark's birthday party who then appears in his bedroom. The scene was eventually cut because it didn't have any comedy in it.