These aren't exactly cheats but hints but they belong here anyway.
Ending bonuses:
Get all the bottles hidden within a level. A FMV sequence, special move, or background information will be unlocked.
Successfully complete the game to unlock the introduction sequence from the Japanese version of the game.
Find all Thievius Raccoonus pages to unlock the Thievius Raccoonus ending sequence.
Successfully complete all Master Thief Runs to unlock a background FMV sequence.
Invisibility:
Get the fourth page of the Thievius Racoonus and in the Perilous Ascent level, get all 25 Bottles. You can now become invisible while moving slowly.
Skip first searchlights:
At the start of the game, go across the rope to the right after the rock tunnel. Get to the tip then jump far and bash the thug as well as the alarm to shut off the searchlights. You have now skipped the first set of security.
Defeating Clockwerk:
When trying to defeat Clockwerk on the second stage, do not let the rings fool you when they flip. They never change their path.
Keep shooting Clockwerk until a white ray hits one of his body parts. Shoot that part until the ray fades away. Do this four to seven times. Then, go through the holes that he shoots. The hole will twist, but it will not change its path. There will be white rays again. Shoot them, and it will fade. Do this four to seven times. Go through the pathway and do not let the lasers spot you. When you reach his head, wait until it pops up, then attack it with your cane.
Move around the volcano and make sure you stay away from his attacks. When a body part of his has a white aura around it, press Square to do damage. When it goes down and regenerates, repeat the process except this time dodge its circular energy blasts. After Clockwerk goes down again, run towards it using Super Sneaky moves. When you get close enough, whack Clockwerk until he goes down. You should kill him before he can attack you.
Defeating Muggshot:
Go around the sides of the arena and hit the gold mirrors. Do not let him shoot you or the mirrors. When you hit all the mirrors, he will get burnt. Repeat this as many times as needed.
Learn the Roll move from collecting clues and use it when you fight him. He will not be able to hit you while you are rolling. Also, it makes you go faster.
Use the Mine move. Have him stop near the mine, then blow it up. When he laughs, it gives you extra time.
In each round to advance to the next, you must hit all of the mirrors. In the first round, it is a square platform with mirrors. In the second round, it is a square platform with some holes and oddly-placed mirrors. The third round is on the chandeliers, where you must Spire Jump to different lights to hit the mirrors. Muggshot cannot hit you while you are rolling.
Defeating Mz. Ruby:
To get to Mz. Ruby for a whack, you must repeat her pattern of button combinations in order to dodge her energy blasts. This includes pressing Square, Triangle, Circle, X in rhythm with her beat. There are three rounds. When you get close to her, whack her.
Defeating the Panda King:
When you are trying to defeat the Panda King, listen to what he says and fighting him will be easy.
This Boss remains in the middle of the platform. Race around the circular room while dodging his fireworks, then continually whack him when you get close to him. He gains a new attack every round; however these are easily dodged.
Once you are close enough, he will start to attack. When it looks like he is going to spin, jump when he starts moving again (about two seconds). When he raises one hand, move out of the way. When he raises both hands, stay where you are. After you have dealt a good amount of damage, he will blow you back out to the outer ring. Also, when he throws his fireballs, move about five steps to the left or right.
Hint: Defeating Raleigh:
Jump around on the platforms and wait until the fly he ate wears off. Then, swing your cane to hit him. Repeat this as many times as needed.
In the beginning round, run around Raleigh so he cannot flatten you. Whack him with your cane when he becomes small again. For the next round, all of the platforms around the one you are on will disappear. Still try to whack him when he becomes small. The next round has the same idea, except that when Raleigh bounces on a platform, it disappears. The fourth round is the same as the second, however Raleigh now has a spinning tongue technique.
Boneyard Casino:
If you do not already have the Dive attack, go back to the beginning of Raleigh's area and collect all 30 Clue Bottles. After you get the Dive attack, warp back to "Muggshots Turf" and enter the Boneyard Casino. Stay in the plant garden, and try not to attack the thugs because they will get you first. You may have to attack one or two thugs. Use the Dive attack or go behind them and attack with your cane. Keep going along the light fixtures until you see a strange dog house. In front of it is a broken light fixture. Climb on it and press X, then Circle. If you hit a lever, lots of coins will fall down. Keep going through the level until you see a giant spinning "pan". Keep on jumping around and landing on the green piece in front of the treasure key . Every time you land on it, the glass around it will break. After all the glass is broken, get the treasure key.
Extra lives and Lucky Charms:
Go to the "Prowling The Grounds" area at Raleigh's hide out in "Tide Of Terror". Go from the fountain with the funny looking fish and walk up the trail of coins. To the left of the "High Class Heist" mini-level is an extra life. Around the corner there is a tree and a window pane over a patch of thorns. In the window is a Lucky Charm. By repeatedly entering the "High Class Heist" mini-level, and returning to the main area, you can get these items again, as many times as desired.
Extra lives:
You must start with at least one life to do this trick. Go to Sir Raleigh's "Prowling Grounds" and look to the northwest. You should see two trees. Double jump on the end of the stair rail or the twisty sewer thing and jump on the trees. You will see a window. Hit it open with your cane and get the extra life. Go back the same way, in stairway. Stay in the middle, then kill the guard with the flashlight. Go toward "High Class Heist", but do not enter. Look to the west to find another window. Break it open and get the life. Then, kill yourself by jumping onto the spike plant in the same location. Restart and you will be in the "Prowling Grounds" again. Repeat the process to build your extra lives.
Easy treasure:
Whenever you see a hook you can swing on; swing on it with your cane. Note: This only works if you swing on an out-of-place hook.
Good start:
The best way to start a level is to get a Gold Charm. When checking a new place, it is best to have more then one hit. You never know were a foe is hiding. If getting a Gold Charm is difficult, go to the level where you fought your first Boss . There is a charm and lives there.
Saving lives:
Press Start as Sly dies before the scene change, then exit the level. However, this is not useful in the final level.
Moving heads:
You can move Bentley's and Sly's heads when they communicate through the binocucom by moving the Analog-stick on their side (Right Analog-stick for Sly and Left Analog-stick for Bentley).
