Revealing mistake: When Ripley is leaving New York, there is the shot of the ship sailing out of the harbour. Check out the water - one layer has been 'cloned' on top of another.
Revealing mistake: In the final scene when Annie and Sam are exiting the observation deck coming towards the elevators, the New York skyline backdrop which should be visible behind them is missing, and the entire sound stage wall can be seen beyond the observation deck safety railings instead. 'Although the exterior and lobby of the Empire State Building, 350 Fifth Avenue at 34th Street, are the real thing, a slightly larger replica of the Observation Deck was built in a hangar at Sand Point Naval Base on Puget Sound just northeast of - where else? - Seattle.' https://www.movie-locations.com/movies/s/Sleepless-In-Seattle.php. (01:39:35)
Revealing mistake: In Dirk's first sex scene with Amber they are both supposed to be naked except for their shoes. At the end of the scene Amber sits up on the table on which they had sex as a female stage hand wraps her in a robe, and you can see she is wearing black panties.
Revealing mistake: After Johnny leaves, they show Baby standing on the porch of her family's cabin. If you look in the background you see two people waiting for their cue before they start walking. (01:24:30)
Revealing mistake: When Rita pulls the first stack of hundreds out of her purse, she puts it down next to her. The bill on top is very close to looking real, but the bill underneath is very fake looking. (00:44:15)
Revealing mistake: When the notice of impending strike is posted in the town, the American spelling of "labor" is used. A Welsh signwriter would have spelt it "labour."
Revealing mistake: On the way to the party, near the end, they are supposed to be in Alabama when the car gets pulled over, but the officer's badge, shoulder patch, and car all say Georgia State Police. (00:51:45)
Revealing mistake: When Sam trips over in the cemetery, she falls onto Dear Johnny's cracked tombstone. As she pushes down, the 'tombstone' squashes under her hands. (00:27:25)
Revealing mistake: At the party someone asks Marcus his name and he replies 'Vincent' the actor's real name (Vincent Cassel).
Revealing mistake: When they're driving back to the Darcys' in the snow, you can see that as they pass through the village near the house, the snow on the ground is in fact a white ground sheet and has not been pulled up to the edges of the wall surrounding the green. (01:17:25)
Revealing mistake: The film is set in 1997 the year of Diana's death. However there is a scene in where Tony Blair is being driven in a car and you can see a Mercedes through the rear window with an '02' number plate indicating a 2002 model vehicle.
Revealing mistake: Near the end, when Morgan Spurlock says "Why not do away with your Super Size options?" the water condensation runs UP the drink. (01:34:00)
Revealing mistake: When the truck leaps off the ferry, the underside is seen, exposing the still-flaming 'roll cannon' opening in the rear floorboard. This cannon is what caused the rear of the truck to rise, sending the truck flipping through the air. (01:52:30)
Revealing mistake: When Jules and Vincent are riding in the car during the "Royale with Cheese" conversation, it is possible to see the reflection of their car in the background, being towed on a trailer. (00:07:05 - 00:08:00)
Revealing mistake: As the gang is being chased through the "96th Street Station", you can see the true station name "Hoyt" (as in Hoyt-Schermerhorn Sts. Station) on the outer station wall. (00:42:50)
Revealing mistake: When Mike Douglas makes Dr. Sacks answer his cell phone, you can see that Sacks is wearing a wedding band although he wasn't married.
Revealing mistake: Near the start of the journey, there is a shot of Chance and Shadow running through a creek. This is followed by a shot of Shadow coming toward the camera. As she turns off to the left screen, something on the bottom moves with her. It is likely a guide for the cat to follow.
Revealing mistake: When Bethany comes home from the hospital after losing her arm, her dad drives them to the back of the house to avoid the reporters. Bethany has her arm covered up with a throw so it can't be seen. When she gets out of the car, you can clearly see the outline of her entire arm underneath the throw.
Revealing mistake: When Mr. Green pulls out of 28th Street, we see him disengage the "Dead Man's Feature" (by pressing down on the throttle with his hand). However, he does not actually move the control lever to make the train move. In that position, the train is at "idle" and will not accelerate.
Revealing mistake: Just before A-Wax kills the guy in the red sweatshirt, you can see the squibs bulging on his back, underneath the victim's clothing.