Tony Hawk's Pro Skater 3

Unlock All Movies
Go to cheats and enter POPCORN.
(Thanks to RoboPhoenix@aol.com)

Unlock All Stats
Select a character, go to cheats and enter MAXMEOUT.
(Thanks to RoboPhoenix@aol.com)

Unlock Cheat Selection Menu During Pause
Go to cheats and enter MARKECARDS.
(Thanks to RoboPhoenix@aol.com)

Unlock Cheats and Characters
To unlock all cheats type in "markedcards" and to unlock mystery characters type in "freakshow" .
(Thanks to Anthony85212)

Unlock Everything for a Character
ENTER: noneed2play.
(Thanks to Ryan092392@aol.com)

Unlock Hidden Character
When creating a new character, choose the name as "Spencer Hawk" and you'll get a hidden character.
(Thanks to RudeKaiser99)