Create a big fountain:
Place four fountains in a square to create a single large fountain.
Giant robot:
Place a Large IG tower next to a radar station and to get a giant robot.
Space shuttle launch pad:
Place two radar stations next to each other to create a space shuttle launch pad.
Ghost train:
Set the Windows system clock to October 31st and watch out for the ghost train.
Holiday pieces:
Set the system date to December 25 for Christmas pieces, October 31 for Halloween pieces, and July 4 for desert pieces.
Winter:
Press [Caps Lock] before playing the game. Alternately, set the system date to December 25..
Spring:
Set the system date to Easter Day.
Summer:
Set the system date to any day in the weeks before or after midsummer.
Autumn:
Set the system date to October 31.
Mansion:
Combine two red brick houses to create a mansion.
Pizza car:
Place a boiler unit next to a road. Pizza cars will eventually appear.
Red cars:
Place a gas station next to the road. Red cars will eventually appear.
Yellow cars:
Place a red brick house with 3D windows. Yellow cars will eventually appear.
Loch Ness monster:
Place a normal pond anywhere on the map. Then, place sunflowers surrounding the lake and Nessie will visit.
Circle:
Put four road turn pieces by each other to make a circle.