Neon Genesis Evangelion. When Asuka is forced to live with Shinji in "Moment, Heart, Together", she refers to the sliding door between their respective futons as the impenetrable Wall of Jericho. There's a suggestion that she's Playing Hard to Get but Shinji, having been raised in Japan and therefore not familiar with this movie, misses the hint.
Concentration: The film's title was the solution to the show's very first rebus.
The Love Boat: In "The Old Man and the Runaway/The Painters/A Fine Romance," an old man finds a teenage stowaway hiding in his cabin. He hangs up a blanket between their beds for privacy, saying he got the idea from It Happened One Night.
M*A*S*H: In the seventh season episode "The Billfold Syndrome", Winchester stops speaking to everyone at camp after finding out he's no longer being considered for a slot as chief surgeon at Massachusetts General Hospital, and to drive the point home, he hangs a sheet in the Swamp separating him from B.J. and Hawkeye.
