Indiana Jones and the Kingdom of the Crystal Skull [use spoiler tags, please]

[Alex]

Though now I am having fun finding tributes and homages.

Driving a truck through the jungle: Sorcerer (1977)
Male protagonist: The Thief of Baghdad (1924)
Raft type vehicle down river with rapids and waterfalls: River of No Return (1954)
Monkeys: Project X (1987)
Professor goes all weirdly native/crazy: Krippendorf's Tribe (1988)