Uncharted 2: Among Thieves PS3 Cheat codes

Hint: Infinite Enemies for Trophy Hunters
If you're having trouble getting any of the "X kills per weapon," or Headshot or Survivor Trophies (kill 75 enemies before dying), there is a location shortly after starting Chapter 19: The Siege where you can camp and shoot continuously respawning enemies.
After starting Chapter 19, make your way down the sloping alley to the large courtyard. There is a mounted machine gun uphill on the left constantly shooting at you. Clear out as many enemies as you can and climb up to the right of the door of the building closest to the cliff (on your right as you enter the courtyard). Take cover looking toward the mounted machine gun on the left and use a grenade to take it out.

If you now look slightly right of the machine gun, at the small grass/mud patch before the next building, you will see an enemy running from behind a building from right to left making for the machine gun. Camp here in cover and keep shooting the enemies as they appear from behind the building. They only stop spawning temporarily if one of them reaches the mounted machine-gun (if one reaches the gun, then grenade them to start the respawns again). Beware: it will stop permanently if you go further to the right, triggering the RPG/wall collapsing cutscene.

If you've already beaten Chapter 19 at the difficulty you're playing, purchased weapons in the store and unlocked the "Infinite Ammo" tweak, then you can use these to get the weapon/kills Trophies.

Da Slaya' Man
Easter Egg: Uncharted 1 Signage
On the "Urban Warfare" chapter and "Their Coming With Us" chapters, the climb-able signs hold references to Uncharted 1. For instance: Club Raja (Which references Eddy Raja from the first game) and Hotel El Dorado (which references the MacGuffin of the first game).

Cheat: Use Tweaks on Any Difficulty
Normally, when you beat the game on a certain difficulty you'll be able to use Tweaks in a new game set on that difficulty. However, if you start a new game on a difficulty you haven't beaten, you can still enable Tweaks. Play until you have a real gun and then switch the difficulty to a mode you've beaten and enable your Tweaks. Save and quit, then set the difficulty back tot he harder version on the Main Menu. When you return to the game, your Tweaks will be enables on that harder mode.

Will Sawyer
Hint: Run While Crippled
On chapters where Nate is injured, if you carry a propane tank you'll be able to run without hindrance.

Unlockable: Multiplayer Taunts
The following taunts can be unlocked by performing the actions below. After they are unlocked you may purchase them in the Multiplayer Store.

"Flex" Taunt - Reach Level 20, then purchase for $50,000
"Flurry" Taunt - Reach Level 30, then purchase for $100,000
"Kiss" Taunt - Reach Level 10, then purchase for $10,000
"Pump" Taunt - Reach Level 53, then purchase for $500,000
"Yes" Taunt - Reach Level 40, then purchase for $250,000

Unlockable: Multiplayer Characters / Skins
The following skins can be unlocked by performing the actions below. After they are unlocked you may purchase them in the Multiplayer Store.

Cameraman Jeff - Reach Level 30, then purchase for $100,000
Doughnut Drake - Reach Level 60, then purchase for $2,000,000
Genghis Khan Villain Skin - Beat Crushing Difficulty. Cost: 1,500,000
Harry Flynn - Reach Level 20, then purchase for $50,000
Heist Drake - Reach Level 10, then purchase for $20,000
Heist Flynn - Reach Level 20, then purchase for $50,000
Karl Schafer - Reach Level 50, then purchase for $1,000,000
Lieutenant Draza - Reach Level 50, then purchase for $1,000,000
Marco Polo Hero Skin - Get the Platinum trophy. Cost: Free.
Skelzor - Reach Level 60, then purchase for $2,000,000
Winter Chloe - Reach Level 20, then purchase for $50,000
Winter Drake - Reach Level 40, then purchase for $250,000
Winter Elena - Reach Level 30, then purchase for $100,000
Winter Flynn - Reach Level 30, then purchase for $100,000
Zoran Lazarevic - Reach Level 40, then purchase for $250,000
Zorskel - Reach Level 10, then purchase for $20,000

Unlockable: Bonus Money for Old-School Players
In the store, hit SQUARE button to check for Uncharted: Drake's Fortune save data. You'll be rewarded with the following bonuses.

$20,000 - Load Uncharted 2 on a hard drive with a game save for Uncharted: Drake's Fortune
$80,000 - Load Uncharted 2 on a hard drive with a completed game save for Uncharted: Drake's Fortune

Unlockable: Multiplayer Boosters
The following Boosters can be unlocked by attaining the levels below. After they are unlocked you may purchase them in the Multiplayer Store.

Point and Shoot (Booster Slot 1) - Reach Level 2, then purchase for $2,000
Bandoleer (Booster Slot 2) - Reach Level 4, then purchase for $2,000
From the Hip (Booster Slot 1) - Reach Level 6, then purchase for $5,000
Scavenger (Booster Slot 2) - Reach Level 8, then purchase for $8,250
Break Up (Booster Slot 1) - Reach Level 10, then purchase for $11,250
Keep Firing (Booster Slot 2) - Reach Level 12, then purchase for $14,250
Down the Irons (Booster Slot 1) - Reach Level 14, then purchase for $18,750
Fleet Foot (Booster Slot 2) - Reach Level 16, then purchase for $23,250
Hell Blazer (Booster Slot 1) - Reach Level 18, then purchase for $27,750
Explosive Expert (Booster Slot 2) - Reach Level 20, then purchase for $32,250
Turtle (Booster Slot 1) - Reach Level 22, then purchase for $40,500
Treasure Bearer (Booster Slot 2) - Reach Level 24, then purchase for $43,500
Sure Foot (Booster Slot 2) - Reach Level 26, then purchase for $52,500
Launch Man (Booster Slot 2) - Reach Level 28, then purchase for $58,500
Sure Shot (Booster Slot 1) - Reach Level 30, then purchase for $64,500
Monkey Man (Booster Slot 2) - Reach Level 32, then purchase for $72,000
Walk Softly (Booster Slot 1) - Reach Level 34, then purchase for $79,500
Scoped In (Booster Slot 2) - Reach Level 36, then purchase for $87,000
Juggler (Booster Slot 1) - Reach Level 38, then purchase for $94,500
Deposit (Booster Slot 2) - Reach Level 40, then purchase for $98,250
Rapid Hands (Booster Slot 1) - Reach Level 42, then purchase for $111,000
Rocket Man (Booster Slot 2) - Reach Level 44, then purchase for $120,000
Situational Awareness (Booster Slot 1) - Reach Level 46, then purchase for $129,000
Revenge (Booster Slot 2) - Reach Level 48, then purchase for $134,250
Evasion (Booster Slot 1) - Reach Level 50, then purchase for $210,000
Veiled (Booster Slot 1) - Reach Level 51, then purchase for $300,000
Invalid (Booster Slot 1) - Reach Level 52, then purchase for $350,000
Half Loaded (Booster Slot 2) - Reach Level 54, then purchase for $400,000
Glass Jaw (Booster Slot 1) - Reach Level 56, then purchase for $1,500,000
Come Get Some (Booster Slot 2) - Reach Level 58, then purchase for $2,000,000

Gobble172
Cheat: Infinite Money
Once you have beat the game you'll get the chance to guy buy things like weapons from the store. You make money by doing things like finding treasures etc.

Once you do something that gives you a large amount of money (like Master Ninja for 25k). Save your game (if it's not at an auto save area) and then quit back to the main screen. Then load up the game again you'll keep getting the reward each time you do it. Soon enough you'll have enough money to buy everything without having to find all the treasures.

IGN Guides
Hint: The Strange Relic
The Strange Relic is back in Uncharted 2 -- you can find it in the sewer in Chapter Five.

IGN Guides
Hint: Marco Polo's Rich Legacy
You'll encounter a pool on the roof of a hotel during Chapter Six. Be sure to jump in it and swim around when you encounter it. Chloe and Nate will play an impromptu game of Marco Polo, and you'll earn $10,000 in-game to spend on bonuses as a result.

IGN Guides
Unlockable: Crushing Difficulty
To unlock Crushing Difficulty, beat the game once through on Hard Difficulty.