Type "themanwiththegoldenswiv" during game play to display the cheat menu. Alternatively, enter "SWIV AND LET DIE", "FromSCIWithLove", or "SWIV!AndLetDie" (case-sensitive) as player names and press [F11] or [F12] during game play. The cheat menu has level selection and any weapon options. Note: Enabling cheat mode through the player name feature will result in a score of zero.
Killing SAM sites
When you see a SAM site, allow it to aim at you. When it does, fly right over the top of it and it will not turn around. You can now destroy it without getting too badly damaged.