Trivia: In the scene when they are in the chamber with the aliens, there are mini R2D2- and C3P0's on the chairs.
Trivia: The young Henry nicknamed himself "Mutt, which is also a term for a dog. Indy named himself after a dog he had as a child that was called Indiana (as noted in the third movie). This is the first hint about their relationship.
Trivia: Among the artifacts that fall out of the crates Spalko and gang push aside in the warehouse scene is Moses's staff. Property master Douglas Harlocker modelled it after the staff wielded by Charlton Heston as Moses in Ten Commandments. Incidentally, the Indiana Jones videogame, 'Indiana Jones and the Staff of Kings', is about Indy's quest for Moses's staff.
Trivia: Before production started and while the movie was still being planned, Harrison Ford was shown the original Indiana Jones costume from the first movie, and he has said he was pleasantly surprised that he could still fit into it perfectly despite being much older, so all doubts he might have had about "fitting into the role" went out the window.
Trivia: When Indy and Mutt are riding the motorcycle through the study hall, they almost run over a nerdy, book-carrying student who gives the "Wilhelm Scream". This classic scream has been frequently heard in movies for at least the past three decades.
Trivia: The girl who punches Mutt during the diner scene is Steven Spielberg's real-life daughter Sasha.
Trivia: This was the first Indiana Jones film without Pat Roach. Roach appeared in the first three films and even played two different characters in 'Raiders of the Lost Ark'. He died in 2004.
Trivia: The Crystal Skull that everyone carries around and the Crystal Skull that is attached to the head of the Crystal skeleton at the end are actually of different sizes. Director Steven Spielberg said that no one would notice.