Trivia: If you stay a little bit into the credits, there is a nice thank you speech from the person who plays Rocket.
Trivia: The movie the guys are watching on the autocinema on Bob's first date is the Mexican film "Y tu mamá también" (And your mother too), directed by Alfonso Cuarón, who also did Harry Potter and the Prisoner of Azkaban.
Trivia: At the end you can see that the movie is dedicated to Herb Flynn. He died of cancer before the movie was released (2003) and acted in various Farrelly brothers' movies: Stuck on you, Me, Myself & Irene, Shallow Hal and There's Something About Mary.
Trivia: The line "...two dip shits stuck together" was edited in from an earlier outtake. This explains why we never actually see Greg Kinnear say this in the film.
Trivia: Bobby Farrelly has a cameo role as one of the brothers in goalie pads during the hockey scene.
Answer: It's the Billy Stewart version of "Summertime" from George Gershwin's opera "Porgy and Bess".
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