It's an ancient Mazatec secret passed down verbally from video editor to video editor: If you want your game to be a smash hit, end your trailer with something roaring. It can be an alien, a dragon, a balrog, a T-Rex, whatever; as long as it's roaring, you'll move a minimum of 20 million units, guaranteed.

One of the core functions of a computer processor is to perform the basic arithmetical functions of the system. Why would we want a processor that gets those basic calculations wrong? Carnegie Mellon's Joseph Bates has the answer.