Mortal Kombat Trilogy

At the story line screen, press RUN-BLK-BLK-RUN-HP-LP. You'll hear Shao Kahn say, "Outstanding." Now press Start and go to the Options screen. You'll see a block with a blue question mark with the following secret options: Level Select, Throwing, Unlimited Run, Bloody Kombat, Smoke, Khameleon. You can toggle these on and off.