Unlimited turbos:
Press R2, L1, Square, Triangle, R1, L2, L1, R2 at the main menu.

Large tires:
Press Square, Triangle, Square, Triangle, R1, R1, L2, L2 at the main menu.

Small cars:
Press Square, R2, L2, Triangle, Triangle, L2, R2, Square at the main menu.

"Dude" sounds:
Press R2, R1, L2, R2, Square, Triangle, L1, R1 at the main menu.

TowJam car:
Press Square, Triangle, L1, R1, L2, R2, Square, Triangle at the main menu.

Flat shaded graphics:
Press L1, R1, L2, R2, L1, R1, L2, R2 at the main menu.

How to Get The ROCKBUSTER:
In the race road to rustwell, after the jump that gets you wicked air, you go through the first barn thing you see the jump DON'T go off it. Yougo around the high end of it and hit the lighter colored piece of the house to your right and ram it. Then you see the ROCKBUSTER. Run into it and you have it!

Secret Codes
Unlock Tow Jam - TWJM Unlock All Secret courses and cars - PWDTST

Unlock the Twinmill 2
Enter the password: TH4T_ROCKS