Turn Lara exactly North according to her compass, then enter the inventory screen. Highlight the "Large Medipack" selection, hold L1 + L2 + R1 + R2 + Down, then exit the inventory screen. Note: An easy way to have Lara face exactly North is to have her hang from something facing North. -From: egmariano.com

Note 1: Enable the weapon code(s) desired, then saved the game and disable the weapon code(s).

Note 2: This code enables Lara to climb almost any wall.

Note 3: This code enables Lara to monkey bar across any reachable roof.