"Slime Day" contains several references to Nickelodeon, the channel that created this show: When Fanboy stutters the name "Nickelodeon" when he reads the copyright message on the slime, he's doing it in the manner of the classic Nickelodeon jingle from the 1980s/1990s. At the end of the episode that original Nickelodeon jingle plays. Also, Fanboy and Chum Chum go to the real Nicklelodeon Studios.
The first part of the "Slime Day" is complete animated, while the second half has the animated Fanboy and Chum Chum in the live-action world. They interact with two live-action people: a security guard and the "Nickelodeon president". Although both roles are uncredited, the guard is played Don Newhouse, a real parking lot security guard for Nickelodeon who once made a cameo appearance in a SpongeBob SquarePants (1999) episode (and was the model for "Old Kid" in Invader ZIM (2001), and the "president" is likely played by an old You Can't Do That On Television cast member.