Unlock all bikes:
     At  the  Bike  Selection  Screen,  press  Up, Left, Up, Down, Up,
Right, Left, Right, Y.

Unlock all styles:
     At the Style selection screen, press Left, Up, Right, Down, Left,
Down, Right, Up, Left, Y.

Unlock Slim Jim:
     At Rider select, press Down, Down, Left, Right, Up, Up, Y.

Unlock all levels:
     At the Level selection screen, press Left, Up, Right, Down, Left,
Down, Right, Up, Left, Y.

Bail in mid air:
     To  do this you have to press and hold the LEFT and RIGHT trigger
buttons then press Y while holding them, all while your in the air.

Get Cheat Menu Items:
     Beat the game with the following characters to unlock a new cheat
at the cheat screen:

Joey Garcia        Ghost rider  
Troy McMurray      Exorcist mode  
Shaun Butler       Night vision mode 
Tim Mirra          Silly grunts  
Mike Laird         First person view  
Leigh Ramsdell     Big crashes 
Kenan Harkin       Sticky crashes  
Chad Kagy          Bike suspension mode  

Get Movies:
     Finish  the  game  with  the  following  characters  to  get  the
indicated movie:

Dave Mirra         Get Dave Mirra movie 
Ryan Nyquist       Get Ryan Nyquist movie 
Amish Boy          Get Programmer movie 
Slim Jim           Promo movie