Revealing mistake: Before Paxton is hit with the 3 prong instrument, you can see the bloody holes already on his shirt. (01:01:20)
Revealing mistake: Aboard the Hogwarts Express, when Harry stands beside the open window and sends Hedwig off with the letter for Sirius, surely his hair and clothes would be wildly moving about, because of the strong wind from the fast moving train.
Revealing mistake: Towards the end when Harmony calls Perry's phone as she's lying on the ground, Harry grabs the phone and looks at the caller ID to see her name. Unfortunately that's not the display showing who's calling. Anyone who has a Nokia phone will recognise that that's showing the contact list with just two entries - Harmony and a random number. The fact that it says "contacts" at the top of the screen is a bit of a giveaway.
Revealing mistake: When Stevie's car is hit by the delivery truck, the side shot that shows the car beginning to roll reveals there is no engine in the car, as we can see through the front fender wells to the truck as it passes on the far side of the car. (01:15:40)
Revealing mistake: When Gretchen turns around while on the bed, a shard of glass in the frame flaps in the wind.
Revealing mistake: When Chelsea is on the roof of the house and Kathy joins her, Kathy's hair is blowing in the wind, while Chelsea's stays perfectly still, the water in the lake is also perfectly still. Obviously the director had the actors do the scenes separately until we see them both together in which case both characters hair is blowing around. (01:27:40 - 02:00:00)
Revealing mistake: When Ben falls from the roof and into the leaves during the storm, you can see the mat that he lands on move from under the leaves.
Revealing mistake: After Majid commits suicide, he is breathing.
Revealing mistake: When Hayden is talking to the Psychiatrist in the Hospital, he is wearing some type of white powder face makeup to make him appear more "ghostly". This makeup was only applied to his face. Whenever they show a side shot of his face and neck during this scene, you can see the demarcation (line) of where the white powder face makeup ends and his natural darker tan neck begins. (01:05:20)
Revealing mistake: After Majid commits suicide, when he is on the ground, you can CLEARLY see him breathing. I mean, it isn't even funny how much you can see him breathing.
Revealing mistake: In the very first scene, which takes place in a Moroccan sheepherder's meadow, the camera makes some gentle panning motion. The mountains in the distance can be seen noticeably moving not quite in sync with the foreground. The foreground is actually in Texas (according to the director's commentary), and the mountains were added in post production.
Revealing mistake: When the phone rings in the motel room, the red light on the phone does not blink which is how those phones work.
Revealing mistake: Katherine shoots Charlie twice to kill him at the end of the movie. Yet if you look at the chambers on the side of the gun, you can see all of them are empty.
Revealing mistake: After the car chase, the authorities are seen carrying away two body bags that are clearly empty. The men show no strain at all in carrying the bodies, and the bags even look empty. But if they were, they'd just be folded up and taken by one person.
Revealing mistake: In the beginning of the movie, at the scene in the morgue, dead David's eyelids very slightly shake right before his casket is closed. (00:04:20)