All Night Nippon Super Mario Bros. Cheats

Each time you beat World 8-4, the game adds a star to the All Night Nippon Super Mario Bros logo on the title screen.
When you have eight stars, go to the title screen and hold A and press START on the controller

If you are out of lives but want to continue playing. Press and hold the A button at the Game Over screen and press Start. You will start at the beginning of the world you played last.