When Brennan and Dale are in their room, showing each other their night vision goggles and autographed sword, the camera pans around while the characters are walking, and a Hugalo's Pizza car light is on top of the chest of drawers in the room. Will Ferrell's character worked for Hugalo's Pizza in Talladega Nights: The Ballad of Ricky Bobby (2006), after he lost his job as a race car driver.
During the commentary on the Blu-ray, it is revealed that the testicles used to teabag Dale's drum set, were real prosthetic balls that cost the crew twenty thousand dollars, complete with real human hair. Will Ferrell is the owner of this prop, and in the same commentary, claims to have brought them out at dinner parties, causing some guests to leave the events altogether.
In the commentary, Adam McKay said that they originally went to Catalina Island for location shots, and discovered that he didn't really like it. Instead, they shot on the coast. Catalina Island appears in several shots, and McKay chose not to have it digitally edited out, as a joke.
The name of the high school, in which Brennan (Will Ferrell) performs during the talent show, and gets made fun of by Derek (Adam Scott), is Great Valley High School, which is the name of the High School Adam McKay attended.
The movie is set in 2008, and Brennan is thirty-nine. When he is seventeen (twenty-two years earlier) and Derrick is fourteen, Derrick performed "Ice Ice Baby". The year of the talent show would have been 1986. "Ice Ice Baby" was released in 1990.
During Dale's job interview, Ken Jeong says he knows of a catering company that is looking for people. This is a reference to Ken Jeong's character (Alan Duck) in the series Party Down (2009), who owns Party Down Catering. Adam Scott is also in Party Down (2009), as a caterer.
Brennan says he smoked pot with Johnny Hopkins and Sloan Kettering. There is a Memorial Sloan-Kettering Cancer Center in New York City, which is also mentioned in the lyrics to the opening song "A-Punk" by the New York City band Vampire Weekend, and although it's not exactly called "Johnny", the famous Johns Hopkins hospital is in Baltimore.
When Richard Jenkins and Mary Steenburgen are removing their clothes after the lecture in the beginning. Richard says, "I collect coins". In Dear John (2010), he plays Channing Tatum's dad, who suffers from Autism, and has an obsession collecting coins.
Kathryn Hahn (Alice) and Adam Scott (Derek), who play husband and wife, appear alongside Ben Stiller in The Secret Life of Walter Mitty (2013). Hahn as Walter's sister, and Scott is the takeover director for Life Magazine.
Running gags in the film include Brennan and Dale drinking a blue juice and Pepsi respectively, the duo fighting, the duo sharing same interests like porn magazines, pop culture, sports, and being in a band, the duo trying to set up a band, failing interviews, trying to stop their house from being sold by Brennan's brother Derek, sleep walking, and getting on their own parent's nerves, especially Robert.