You can speed up Pac-Man and Ms. Pacman or enable fast shooting in Galaga by entering this code after inserting coins. Once you enter the code, you should hear a sound indicating that the code worked. Now just select a game and enjoy! Credit goes to GinsuVictim for posting this on the cheat page for Namco 20 Year Reunion: Ms. Pac-Man/Galaga - Class of 1981.

Code	Effect
Left, Right, Left, Right, Up, Up, Up, Fire	Enable speedup.