Code Effect
Make Me Sick [sick] All guests become Sick and vomit immediately
Atari [laugh] All guests Laugh
Mouse [look down] All guests stand around looking down at the ground
Frontier [rides] All rides and coasters never break down
Atomic [attack] Big Explosion - makes a huge explosion on a coaster crash
Andrew Thomas [rct1] Decreases track friction, which can help when importing some RCT1 or 2 coasters into RCT3. Only works after Update #1.
ATITech [fast] Every Person (both guests & staff) move super fast,
Guido Fawkes [fireworks] Gives access to the advanced Fireworks editor
John D Rockefeller [$10,000] Gives you $10,000
Chris Sawyer [joy] Guests Jump for joy
Melanie Warn [guests] Increases Guests' Happiness
D Lean [routes] Open the "Flying Camera" routes editor
Simon Foster [rides] Pains Pictures of Rides
Jonny Watts [cam] PeepCam (see the world through the eyes of the guest who you just renamed)
Sam Denney [coasters] Peeps ride all coasters
Jon Roach [non rides] Peeps ride all non-coaster rides
Andrew Gillett [reduces] Reduces friction to none on all rollercoasters
John Wardley [coasters] Removes height restrictions when building coasters
FPS [show frame] Shows Frames Per Second
David Braben [chain lift] Unlimited launch and chain lift speeds (only works after update #1)
Katie Brayshaw [guests] Waving Guests
James Hunt [buugy ride] You are given a buggy vehicle to ride in - exit coastercam and delete as scenery when done.