Paperboy 

Level select 
Enter "MAXSUBS" as a code. After this code is activated, enter the Alice's RV Haven level.
The game will automatically mark the level as completed.
Exit the level to unlock all remaining levels in the game.
Alternately, enter "OBVIOUS" as a code.

Invincibility 
Enter "INVINC" as a code. Infinite papers on all levels Enter "NOBUNDLE" as a code.

View all headlines 
Enter "HEADLINE" as a code.

Super jump 
Enter "MOON" as a code.

Super Jump Springs 
Enter "ALLJUMP" as a code.

Rocket Boosters 
Enter "GOFAST" as a code.

Turbo mode 
Enter "RUSH" as a code.

Slow-motion mode 
Enter "WAKING" as a code.

Frame-by-frame mode 
Enter "UNTIMED" as a code. Then while playing a game, press C-Right to advance to the next frame.

Near-sighted mode 
Enter "MAGOO" as a code.

Invisible obstacles 
Enter "JUMBLE" as a code.

Screaming obstacles 
Enter "SCREAM" as a code.

Cartoon sounds 
Enter "THUMP" or "THUNK" as a code.

Random paper tossing 
Enter "RANDOM" as a code to hit the nearest object that will react (such as a homing device) on a power throw.

Throw papers backwards 
Enter "BACKWARD" as a code.

Throw papers directly in front of character 
Enter "FRONTS" as a code.

Throw papers at 90° angle 
Enter "SIDES" as a code.

Big newspapers 
Enter "SUNDAY" as a code.

Small paperboy/papergirl 
Enter "LITTLE" as a code.