Revealing mistake: In the hotel meeting scene, the Grand High Witch tells the witches they can take their wigs off. When we see the newly bald witches, it is particularly obvious that only the foreground witches are ladies with bald caps - the rest of the witches are bald men. (00:30:10 - 00:31:00)
Revealing mistake: When all four actors are up on the rooftops, look closely at them when they all step onto the smoke platform that brings them down. All four actors are doubles. (01:46:50)
Revealing mistake: When Scooby, Shaggy, Mary Jane, and Daphne go crashing through the window while running from the two monsters, the falling glass and broken window frame pass right through the CGI Scooby. (00:42:30)
Revealing mistake: When Augustus is leaving the factory, he is wearing a brown colored glove on the hand he gnaws on. You can see the seams in the glove.
Revealing mistake: When the Telmaries are building their war machines, there is a shot of a two-man saw being used to cut timber. There is no sawdust falling from either the saw blade or the wood itself. (00:46:30)
Revealing mistake: When the TVs explode, the glass is very fake and "cardboardy".
Revealing mistake: After Lansbury makes her clothes start to move, her nightgown attacks someone and you can notice the strings that make the gown move.
Revealing mistake: When the professor is trying to find the gremlin, he is in the room with the movie playing. The projector that is playing the movie is actually moving backwards. (00:44:35 - 00:47:35)
Revealing mistake: When Ash shoots Cheryl through the door in the head, you can clearly see the hose (not an artery) that's squirting out the blood. (01:16:14)
Revealing mistake: Whenever Rudolph is walking you can see the tracks he makes before he even puts his feet down.
Revealing mistake: The stepmother's arm disappears for a split second when she tells her daughters that there is still a chance for them to become the princess.
Revealing mistake: When we first see Max, his paws are leaning on a balustrade and become transparent. Though it may seem like it's an optical effect because they're in the shadows, the next angle shows them fully lit and opaque.
Revealing mistake: When the old couple who give Wolverine clothes are first driving towards their house, there is an aerial shot of them driving over a bridge. This is supposed to be set in Canada (drive on the right) but it was filmed in New Zealand (drive on the left). They are driving on the right but the arrow on the road is on the left side.
Revealing mistake: In many scenes, particularly the dance scene in the bar, Michael's wings disappear and/or reappear. If you look closely throughout the movie, his wings are often completely gone.
Revealing mistake: In one scene, when Jack is in the dungeon talking to the fairy, you can clearly see that the "fairy" is nothing more than a light on a thin piece of wire. The wire can be seen quite clearly for two shots.
Revealing mistake: Any time when the two girls are in hell's corridors and running around, you see these corridors as stone walls, yet whenever they back up against one of these walls, you can clearly see they are merely rubber sheeting overlayed on a framework as the rubber sheeting bends and contracts very clearly.
Revealing mistake: When Thunderbird 3 lands in London, the jets do not burn the grass they land on.
Revealing mistake: In the scene when Christine smashed repeatedly into the silver Camaro at the gas station, there is no motor in the Camaro. The hood of the Camaro gets knocked off the hinges and is twisted sideways on the car. As Christine is in reverse and dragging the Camaro along you can see down through the hood that the engine compartment is empty. Minus a transmission also, I believe. (01:15:30)
Revealing mistake: When Shrek and Donkey are sitting by the fire and looking at the stars, when Donkey asks Shrek about "our swamp" and Shrek says "We?" When Shrek blinks, his right eyeball is slicing through his upper lid. (00:46:30)
Revealing mistake: When Gary and Wyatt come home and see Chet turned into a pile of poo, Chet shoots his tongue from his mouth and catches a fly. Look closely, the tongue flies completely out of his mouth and is attached to a metal spring. (01:24:55)