Continuity mistake: The T-1000 punches his body through the window of a helicopter to get inside. An instant later, the hole in the windshield is gone. (01:56:35)
Continuity mistake: After defeating Fulton Balcus, Sean removes the armor and has no clothes on. As Sean and Mizky leave, Sean is wearing sneakers. Mizky only brought him a shirt to wear.
Continuity mistake: After the bird of prey first fires on Enterprise, Kirk is thrown right out of his chair to his left and lands on the floor. The camera pans around the bridge briefly, seeing the rest of the crew staggering and holding onto things. In the very next shot Kirk is back in his chair shouting "back off, back off" and the crew back in their positions as if nothing has happened.
Other mistake: There is a patch on the jacket Harley (Rourke) wears, that appears and disappears throughout the movie. It's on the front lower right side. It is there when he's standing outside their friends' bar with Marlboro, it's gone when they are inside.
Other mistake: When Eve runs into the BMW from behind, the guy slams into his steering wheel. When you are hit from behind, you will slam backwards into your seat. It happens twice, the third time the airbag deploys and stays inflated (real airbags deflate in a second, they are not balloons).
Factual error: When Peevey gets stuck in the truck, Cliff fires up the rocket pack and simply pushes it clear. If the rocket pack can push out enough thrust to move a 2 1/2 ton truck, Cliff's body can't take that kind of stress. He stretches his arms out, starts pushing, and sets off the rocket, putting himself between the truck and an accelerating rocket demonstrably capable of moving it. The truck is stationary so has 2 1/2 tons of inertia. The rocket instantly accelerates it to an appreciable speed. Human arms cannot take that kind of stress. He's going to be crushed.
Continuity mistake: When the Turtles first arrive on screen behind Keno, they leap over the boy to attack the thieves. Their order from left to right when they walk up is Mikey, Leo, Donny, then Raph. The very next shot shows them in the air, and the order is now Mikey, Donny, Leo, then Raph. Donny and Leo switched places between shots. (00:03:35)
Other mistake: Just before the evil robots capture Bill and Ted's girlfriends, after they crash through the window, the girlfriends ask the robots: "Who are you?" and Bill goes "Well, I'm really Evil Ted!" and unzips himself and out pops Evil Ted, and the other robot goes, "And I'm really Evil Bill!" and out pops Evil Bill. When the robots are herding the girlfriends out just before knocking them out with their breath, you can see two sets of clothes in the bottom left corner if you watch closely.
Continuity mistake: When the old woman is cooking she is stirring the casserole. When it cuts she is spicing the food. (00:20:45)
Continuity mistake: During the big fight scene near the end, the baddie manages to drop the hero down an elevator shaft in a warehouse. The scene ends with a shot looking up the shaft at the bad guy laughing demonically, looking pretty mucky and with hair all over the place. Cut to the next scene where the bad guy appears in a room where the shield beam is generated. Now he is completely clean, has a different hairstyle, and if I remember right has a completely different costume on. (This is because the final fight is actually a combination of two separate scenes - the scene in the elevator shaft was originally meant to come halfway into the film, but the scenes around it were cut, so it was added into the final battle. It has been restored to its original place in the "Renegade" cut of the film, but this mistake is still present in the theatrical version).
Visible crew/equipment: When Frank and Tracy are about to surrender at the hotel and the cops start shooting, Frank yells "What the hell is going on here?" Frank then hides behind the car and you briefly can see the boom mike reflected in the car window. (00:52:20)
Visible crew/equipment: When Wanda comes into the room and Blade comes after her, a lamp drops off the table when she knocks it, but before it completely falls, a crewmember's hand can be seen grabbing it. (01:04:15)
Other mistake: When the paperboy throws a newspaper at Hulk Hogan, and he throws it back, hits him and he falls off his bike into a bush. If you look closely, you can see him run into the bush, instead of being knocked into it.
Continuity mistake: David goes downstairs and finds out about his surprise birthday party. The tape recorder and the other objects on the table change position between shots around the ugliest cake ever. (00:05:25)