!!The film contains these examples, which have been deemed to be Trivia:

* AllStarCast
* HeyItsThatGuy: Would you belive Bob Vaughn is actually the voice of [[Film/WhoFramedRogerRabbit Roger Rabbit?!]]
** John Getz as Templeton Peck who you'll see again in Fincher's ''Film/TheSocialNetwork''
** [[Film/TeenageMutantNinjaTurtles Casey Jones]] (Elias Koteas)
** [[GroundedForLife Sean Finnerty]] (Donal Logue)
** [[Film/{{Fargo}} Norm Gunderson]] as a convicted sex offender [[spoiler:and possibly the Zodiac's secret identity]]. Who knew?
** [[OneTreeHill Mouth]] is shot by the Zodiac and lives to tell the tale.
* TheOtherDarrin / TheOtherMarty: Intentionally done with the Zodiac killer being played by different actors through the film to match what eyewitnesses said.
* TomHanksSyndrome: John Ennis, Philip Baker Hall, Dermot Mulroney, Donal Logue, Charles Fleischer, Anthony Edwards and Creator/JohnCarrollLynch are best known as comic actors.
!!From [[WebComic/{{Zodiac}} the webcomic]]:
* OneOfUs: Eggplantman, the author, acknowledged the existence of Website/TvTropes, giving direct links to this page in his Website/DeviantArt commentary, and provided the current image.