Cheat mode:
Rename a guest to one of the names:

Result - Name:

Big explosion - Atomic
Peeps take photos - PhotoStory
Display frame rate - FPS
Get the buggy - James Hunt
All peeps laugh - Atari
Peep jumps for joy - Chris Sawyer
Peeps dance - Shifty
Lots of ducks appear - A Hitchcock
All rides and coasters to never break down - Frontier
Remove height restrictions for building coasters - John Wardley
All rides irresistible to peeps - Jon Roach
All coasters irresistible to peeps - Sam Denney
Unlimited launch and chain lift speeds - David Braben
Peep cam; see through eyes of guest - Jonny Watts
Unlock advanced fireworks editor - Guido Fawkes
Increase money by $10,000 - John D Rockefeller
Guests stand around looking down at the ground - Mouse
"Flying Camera" routes editor - D Lean
All guests get sick - Make Me Sick
All guests ride every coaster before leaving - Sam Denney
New staff hired fully trained - Isambard Kingdom Brunel