You type NUMBERONEDACRESTREET at the main menu it brings 
you to a menu and you can get many cheats from there 
including 5 new secret levels...

Hold down SHIFT and type:
Code                  Result 
----------------------------
WIREWEWAITING       - Turns off the textures
WHATSTHEPOINT       - Turns graphics to the dots
SOLIDASAROCK        - Invulnerability
FLATBROKE           - No shading
GOURAUD             - Gouraud shading on
OLDMACDONALD        - Protect farm from jumping COWS !!!
FLYMETOTHEMOON      - Racing in the moon
HAVEALL             - You got it all
SUPERDAISY          - One shot kills 'em all
SUPERSHOOT          - Same as SUPERDAISY
INVUNERABILITY      - That's just what it seems
INFINITELIVES       - And so is this one
INFINITEWEAPONS     - Infinite weapons
MASTEROFTHEUNIVERSE - Atleast it changes textures on & off