Extra multi-player Maps
Get an "A" grade on single player missions to unlock additional multi-player maps.

Drive Or Die Expert multi-player level
At the level selection screen, highlight the multi-player Drive Or Die Expert level, then hold L + R for about three seconds to unlock the level.

Helter Skelter multi-player level
Play 20 or more multi-player games in one sitting to unlock the Helter Skelter multi-player level. When this is done, force the game to save by changing your options or weapons configuration in single player mode to make this level always available.

Bonuses
Successfully complete the challenge games to get bonus items such as a starting drone with 9999 bullets, etc.

Hidden Artwork
Place the game disc in a PC compatible CD-ROM drive to find artwork from the game.