Revealing mistake: When Ben and Ian get the two different fingerprints from two different people, Mr. Ferguson [random security guard] and Abigail Chase, they are the exact same fingerprints. This can be confirmed on the DVD with pause and zoom. Moreover, the two scans show exactly the same emphasis/pressure on different regions within the print, with more light and detail on the left side and little in the center. (00:39:15)
Revealing mistake: When the two vans are driving away from the Archives, Dr. Chase tries to open the door to escape. As the camera pans from her face to the door handle, you can see by the way her hair moves that the quarter-second sequence is run in reverse. (00:48:55)
Revealing mistake: When Ben, Abigail, and Riley are fleeing the National Archives, the window on the driver's side has been shattered by a gunshot. Although they are driving at high speeds, no wind seems to be entering the van to mess up their hair.
Revealing mistake: When the stairs built on the walls of the dumbwaiter shaft start to collapse, Riley makes a jump onto a stable one. In the first shot of him jumping you can see a thick stunt wire attached to the back of his shirt. (01:43:35)