At the blackjack table, when they're counting cards, the scene is a reference to 21, including the floating equations in the background.
Phil calls Allan a Gremlin because of all the rules Tracy has for him.
When Phil and Allan are riding down the escalator to the blackjack table, they're in the pose (with the same music) as Tom Cruise and Dustin Hoffman in Rain Man.
Three Men and a Baby
Nearly half of the movie is a parody of this. Directly referenced when Stu is about to meet his "wife" at her apartment.
Video Feature: One Crazy Night
Rorie and Ryan discuss their favorite "one craaaaaaaazy night" flicks.
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