Enter one of the following codes during game play:

Effect - Code
$1,000,000 (maximum of $10 million) - [Ctrl] + [Alt] + C
1000 upgrades points - [Ctrl] + [Alt] + U
100 landmark bonds - [Ctrl] + [Alt] + B
Add 10,000 to city population - [Ctrl] + [Alt] + A

Note: This code can only be used once.