Atomic Bomberman

Campaign mode select:
Press C five times at the player selection screen.

Level editor:
Hold [Ctrl] and press E six times at the main menu.

Abort losing round:
Immediately press [F10] if your character is destroyed to keep the round from being counted.

Bonus graphics:
Enter the "data/sound" directory of the game to find hidden graphics of the game's programmer.

Bonus themes:
Enter the "data/theme" directory of the game to find Windows theme files for the game.