Toward the end of the movie, there is a scene that takes place in a radio telescope dish. If you watch carefully as the camera pans back showing you the entire dish, you will see a cameraman dropping into a panel almost in the exact center of the dish.
Another blooper in the movie happens with the ax. the ax is first used to hold the door shut. the van backs up into the door breaking the ax and making it fall to the floor. in another shot the ax is then inbeded into the electronic equipment. (ax disappering and reappering)