Roger's character in this episode looks exactly like Dean Haglund's Ringo Langley from The X-Files (1993), a character and show dedicated to conspiracy theories.
In the first scene, Stan's lapel pin is actually inverted to set the tone for conspiracy before the the subject matter is revealed.
At conspiracy-con, there is a booth for "Old Ulysses" which is the monster seen 2 seasons later in s15e17
The title of the episode is a reference to Marvin the Paranoid Android, a popular character from Douglas Adams' comic/sci-fi story "The Hitchhiker's Guide to the Galaxy."