In reference to filmmakers who make joking allusion to their other films, Lucas does this in American Graffiti (a car with a license plate that reads "THX-1138") and again in Star Wars (a Stormtrooper whose number is THX-1138). Spielberg parodies his own Jaws in the opening of 1941 (and does an homage to Kubrick's Dr. Strangelove in his casting of Slim Pickens). And Spielberg plugs Lucas' Star Wars series in both Poltergeist and E.T. through such items as the kids' bedsheets and a Yoda Halloween costume. Some of this is a variation on "product placement," except they're plugging their own films (or, in Spielberg's case, those of their friend). Some may find this self-referentiality either too cutesy or too self-congratulatory, a sort of narcissistic intertextuality. It smacks too much of the in-joke (for those in the know) or advertisements for themselves. Andrew Gordon