Holiday pieces -
Set the system date to December 25 for Christmas pieces, October 31 for 
Halloween pieces, and July 4 for desert pieces.

Ghost train -
Set the Windows system clock to October 31 and watch for the ghost train.

Winter time -
Press [Caps Lock] before playing a game.

Create a big fountain -
Place four fountains in a square to create a single large fountain.

Space shuttle launch pad -
Place two radar stations next to each other to create a space shuttle launch 
pad.

Giant robot -
Place a Large IG tower next to a radar station to get a giant robot.

Loch Ness monster -
Place a normal pond anywhere on the map. Then, place sunflowers surrounding the 
lake and Nessie will visit.