During one scene, after Shari has left, Ed is in his video store and sees a woman in a wig and sunglasses outside whom he recognizes as Shari in disguise. In the background you can see a poster for the movie Vertigo (1958), which features a woman disguising herself in a similar fashion.
There are two tributes to Don Knotts in the film. The Ghost and Mr. Chicken and The Incredible Mr. Limpett are shown on the video store counter. An advertisement for "Fife" is shown on the screen. Don Knotts played Barney Fife on the Andy Griffith show, also starring Ron Howard.