Continuity: When Mike first enters room 1408, there are three light switches on the wall. He flicks on two of them. A few seconds later, you see the switches behind him, but it is two different switches that have been flicked.

Continuity: When Mike opens the laptop, the screen is folded slightly backwards, in the following shots its positioned in a straight angle. Submitted by Sacha

Continuity: After slamming his hand in the window, mike bangs on the front door leaving blood on the left side of the map on the door. Later in the film, there is blood on both sides.