All Boarders, Levels, Boards, and Outfits:
At the title screen, hold R1 + L1 and press , , Right, , , Down, , , Left, , , Up, then let go of L1 and R1.

Full Stat Points:
At the title screen, hold R1+L1 and press , , Right, , , Down, , , Left, , Up, then let go of L1 and R1.

Play as DJ Mix Master Mike:
At the title screen, hold R1 + L1 and press , , Right, , , Down, , , Left, , , Up. Then select any character and he/she will be replaced by Mix Master Mike when the level begins.

Play as Rectorator:
Enter your name as RECOR in World Circuit Mode. Then select any character and he/she will be replaced by Rectorator when the level begins

Hints

Gravity Defying Grinds:
In Showoff mode its hard to get gold at first if your not experienced. A very easy way to get gold is to grind everything you can. If you find yourself under a rail that you missed, jump up and back flip. Your board will grab and you'll rail upside down! Don't worry about falling down cause you get the points as soon as your off the rail.

Super Air, Better Tricks:
If you want better air remember one thing.....DON'T FALL. Bust out a lot of tricks and get a lot of rings on your TRICKY scale. Then press and hold the R2 button for about 1 second and press at the same time. Now you're ready, (if you're saying you aren't don't read this then) when you're coming up to a ramp hold down and do the R2 and thing which will give you extra speed. Let go of the buttons and do your "tricky" trick. You can also use the R2 and strategy to get boost.

GameShark Codes

Master Code (Must Be On) 
EC8FA3FC 14303924 

Unlock All Riders 
1CA534C4 61DFB00C 

Unlock All Tracks in Single & Practice Modes 
1CA534C0 61DFB00C 

Thanks to Revolution readers Greg, Tscruggs, Kr0w, Joshua Zeiner, Randy Butz, Jamell, Gray, T-$ and JHud!