Metal Gear Solid 4: Guns of the Patriots/Unlockables

Passwords
These passwords can be entered on the Extras screen from the main menu. Items and weapons will be obtained when you load a save file, or, if you start a new game, when you get the Metal Gear Mk. II. IPod songs will be available immediately.

Secrets
There are many secrets to discover in MGS4, these are only a few, so feel free to add on any that you find!


 * Crop Circle: While tracking Naomi in Act 2, there is a path that leads to a small field, which contains a Crop Circle!
 * Water Treatment: While tracking Naomi in Act 2, there is a path that leads to a small concrete platform, where a PMC Soldier is urinating into the river.
 * Tailing Snake: In Act 3, while trailing the Resistance Member, you may see a figure following Snake. These are the Dwarf Gekko that you see in the cutscene after the Resistance Member leads you to the church.
 * Sunny's PSP: In Act 2 mission briefing you can see Sunny playing her PSP, the game she plays is Penguin Adventure, the first game of Hideo kojima.