Unlock Bungi Game Levels:
Highlight the bungi game on the game select screen, and then press UP, UP, DOWN, DOWN, LEFT, RIGHT.
Unlock Clam Game Levels:
Enter Blast, and then press UP, UP, DOWN, DOWN, LEFT, RIGHT.
Unlock Secret Characters:
Enter Blast, and then press DOWN, DOWN, RIGHT, LEFT, RIGHT, UP, LEFT, DOWN, RIGHT.