Watching a British show "Spooks" and a guy's Beretta magically became a Glock when he handed it to another guy.
I really like how cops on TV yell "Lock and Load!" before they burst through a door. In retrospect, I haven't seen that in a while.
As others have said, TV writers screw everything up. Spies have magical USB drives that can download a terabyte in less than five minutes. People driving cars with standard transmissions shift into high gear and then a minute later shift again and again and again.