Deliberate mistake: In the scene where Alicia Silverstone and Dave Foley are in the porno store, they cut to a guy standing behind a counter. All of the explicit shots of the videotape covers on the countertop are blurred out.
Factual error: After some tinkering with a TV set and a mirror, Calvin Webber finds that he can watch a TV show in reverse image. On the screen is the opening of "The Honeymooners" showing the cast members' names superimposed on a picture of the moon, with Jackie Gleason's face. But the picture is in color, mostly blue and off-white, while the actual "Honeymooners" series was filmed in black-and-white.
Continuity mistake: When Calvin first goes back up to the surface, he encounters the bartender. The bartender is shown as himself moving at first then he freezes while Calvin's light is on him. Again it shows the bartender but you can tell if you look close enough he is just a piece of cardboard falling to the ground. Then Calvin tells the bartender to leave his elevator alone. (00:27:03)
Answer: Adam: Tempus fugit (Latin) = Time flies. Dad: Que les bons temps roulent! (French) = How good times roll! Adam: Geradeaus, dann links (German) = Straightforward, then left. Dad: Sorgen Sie bitte dafür, dass die [das] Gepäck sorgfältig behandelt werden [wird] (German) = Please make sure that this luggage will be treated carefully. Adam: Haben Sie etwas Nettes in Leder? (German) = Do you have something nice in leather?