All cheats of RCT also work in RCT 2:
Name a guest as
Chris Sawyer -- He will walk around taking pictures
John Mace -- He'll pay double prices on rides
John Wardley -- Create a guest that constantly think "wow !"
Katie Brayshaw -- All visitors will wave
Melanie Warn -- Increase the Guest Happiness
Simon Foster -- He will walk around painting pictures.
Damon Hill -- Drives go-karts twice as fast
BigBucks -- Unlimited cash
Tony Day -- Eats lots of hamburgers
Michael Schumacher -- Rides four times as fast :p
Tom Cruise -- Visits all attractions
Bill Gates -- Unlimited money for all visitors