Revealing mistake: In the scene where Doc Brown is following Biff into the tunnel, as Marty starts to pass between the cars on his hoverboard, one of the wheels on the rig supporting the hovering DeLorean is visible. (01:30:30)
Visible crew/equipment: After Indy and Henry have escaped from Castle Brunwald, Indy jumps into one of the boats, pulls the motor starter cord and jumps back out, then just as he bends over to release the boat from the piling, right between Indy's legs the black covered arm of a hidden crewmember appears from under the tarp taking hold of the throttle, steering the boat away from the pier. (01:02:40)
Continuity mistake: When Nick is in the spoon, the milk around him turns green.
Visible crew/equipment: During Bud and Coffey's fight in the lab, we see a lightbulb swinging from side to side between the two men. If you look closely, you can see a hand (belonging to a third person) pushing the lightbulb. The only people in the room are Bud and Coffey. (01:44:16)
Visible crew/equipment: After Bond received a lighter from Felix and Della, he uses it, and the flame is big. In the beginning and the end, you can see a tube is connected to the lighter, and the tube goes into his suit. (00:15:00)
Continuity mistake: Near the end, the Ghostbusters make the Statue of Liberty smash the window on the roof of the art museum before abseiling in. The window gets completely destroyed, but just after Vigo says 'Now we become one' we see the window again and it appears less damaged than before. (01:35:50)
Continuity mistake: When Wallace races to get crackers, check the packet's logo. When the camera angle changes it's different. (00:08:57)
Continuity mistake: When Fuller falls to his death, the mannequin used as his stand-in gets decapitated on its way down. It even makes a loud noise. When Fuller lands, however, his head is still on his shoulders.
Deliberate mistake: When Belloq, Dietrich, and Gobler arrive next to the destroyed Flying Wing, Eric Zala is on Dietrich's right and Gobler on Dietrich's left. In the next shot, they have switched places. This mistake actually exists at the same point in Raiders of the Lost Ark - recreating it was a deliberate choice.
Continuity mistake: During the classroom scene, the spelling of of Genghis Khan's name on the chalkboard changes from "Genghis Khan" to "Ghenghis Khan" between shots. (00:04:50)