Money: Press [Shift] + [F4] + 4 at the screen where POD parts are purchased. 
Note: This can only be used five times after completing each race, regardless of outcome. 
Press [Ctrl] + [F4] + 4 for even more money.

Race as Sebulba: Successfully complete the Galactic Circuit to unlock Sebulba at the racer selection screen.

Taunt Opponent: Select tournament mode. Highlight "Start Race" and press [Space] at the menu. An intermission that features your character and opponent taunting each other will appear. Note: This will not work if your character is the track favorite.

Hint: Ando Prime Shortcut: On any of the Ando Prime Snow levels, do one lap as usual. Then, when you come up to the starting line, veer off to the left and you should see that one of the tents is open. If you manage to go through the shortcut unscathed, you should be comfortably ahead of everyone else. You can repeat this on the third lap also.

Hint: High Floating: On any Oovo IV level just before exiting an anti-gravity tunnel pull up and keep pulling away from the ground and if done right , after exiting you will keep floating in the air hugging the ceiling.