Bazooka in Lara's Bedroom:
(submitted by: bond james bond)
In Lara's bedroom, walk into the fire and press: X, X, X, R1, L1
Enter these codes during gameplay. Do NOT pause

All Weapons:
L2 R2 R2 L2 L2 L2 L2 R2 L2 R2 R2 L2 R2 R2 L2 L2 R2 L2 L2 R2
Lara will scream to confirm correct entry

Level Skip:
L2 R2 L2 L2 R2 L2 R2 L2 R2 L2 L2 L2 L2 R2 L2 R2 R2 R2 R2 L2
Lara says "no" to confirm correct entry

All Secrets:
L2 L2 L2 L2 L2 R2 L2 L2 L2 R2 L2 R2 L2 L2 R2 L2 L2 R2 L2 L2
Lara says "no" to confirm correct entry

Energy/Health Fill up:
R2 R2 L2 R2 L2 L2 L2 L2 L2 L2 R2 L2 L2 L2 R2 L2 L2 L2 L2 L2

Race Key in Lara's House:
R2 L2 L2 L2 R2 L2 L2 L2 L2 L2 L2 R2 L2 L2 L2 L2 L2 R2 L2 L2

All Weapons, Medkits, Flares and Save Crystals:
L2 R2 R2 L2 L2 L2 L2 R2 L2 R2 R2 L2 R2 R2 L2 L2 R2 L2 L2 R2

Secret Room in Lara's Mansion:
When you enter the mansion go to her pool. Behind the diving board there is a switch. Press it to open a door in the main room with a switch behind it. Pull the switch and quickly turn around and sprint for the room across the hall. Inside you'll find some of the artifacts she's collected on her adventures.

Race Course key:
(submitted by: Ken Burgess)
In Lara'a house go into the attic and push the moveable box forward as far as possible. Then go to the study (The room above from the one with the TV etc.) Go to the 3rd shelf on the right after entering and pull out the book. Then go into the fireplace and climb the wall (The fire would've gone out) Go into this newly available area until you find a room with some boxes. Move the upper block to the left, away from the switch on the wall on that platform. Pull the switch and run through the passage opened when you moved the block. You will find yourself in the attic. Carry on running down the stairs into the entrance hall. Under the stairs in the passage that leads to the Gym a door will be oopen if you were quick enough. Go through here into a room with some fish tanks. Move the block under the hole in the ceiling and climb through. Go into the tank ahead and swim around the two corners. You will find the key in here.