Trick N' Snow Boarder Codes -

Resident Evil characters:
Press Triangle(2), X(2), Square, Circle, Square, Circle at the title screen. A sound will confirm correct code entry. Enter free mode, then press L2 or R2 at the character selection screen to access Leon, Claire, or a zombie. Alternately, press Triangle, X(2), Square, Circle, Square, Circle.

Bonus track:
Successfully complete story mode. Then, press L1 when selecting a track to unlock a new track.