WhiteOut

Master code:
Hold R1 + L1 and press Right(4) at the main menu to unlock all tracks, characters, and snowmobiles.
jusdozin.

All characters:
hold L1 + R1 and press Down(4) at the main menu.

All parts:
Hold L1 + R1 and press Left(4) at the main menu.

All tracks:
Hold L1 + R1 and press Up(4) at the main menu.

Win race:
Hold L2 + Triangle and press Up, Down, Left, Right during a race.
jusdozin.

10,000 points:
Hold L2 + Triangle and press Left(2), Up, Down during a race.

Restore stamina:
Hold L2 + Triangle and press Right(2), Left, Down during a race.

Alternate view:
Hold L2 + Triangle and press Down(2), Left(2) during game play.