Continuity mistake: In the scene where Charlize Theron and Christina Ricci are in the car and Christina is driving, the camera pans to Charlize smoking a cigarette. The first shot it is half way done, the 2nd time it is at the filter and then again half way done and then it's gone and she lights a brand new one.
Continuity mistake: Just after they have trashed the red car, Lee and Selby go into the bedroom of the motel and Selby sits on the bed. Lee opens the wardrobe and then starts talking to Selby. If you look closely, you can see the door she opened is sometimes fully open, half open or closed, especially as there seems to be a metallic rack on the inside of it which makes it quite obvious when it's open.
Continuity mistake: When the red Pontiac Grand Am crashes, the car changes model. The red Grand Am they are riding in before they get to the crash scene is a 1992-1995 model (1996s got a facelift). During and after the crash scene, it is a 1989-1991 model. Prior to 1989 the front end was more squared off and the back end was different (1985-1988's had red rear turn signals instead of amber and the license plate was mounted between the taillights, not down below the bumper as it is on 1989-1991's).
Continuity mistake: As they crash the Grand Am, they narrowly miss a blue and a red flag on the right side of the car, leaving them standing. While outside the car, you can see one of each on the ground on the left side of the car. When they drive away, you can see another blue one on the ground.