Fallout: New Vegas Cheats

Little Wheel (10): Play 10 spins of Roulette.
Double Down (10): Play 10 hands of Blackjack.
Caravan Master (30): Win 30 games of Caravan.
The Courier Who Broke the Bank (30): Get banned from all the Strip's casinos.
Hardcore (100): Play the game from start to finish in Hardcore Mode.
Ain't That a Kick in the Head (10): Complete Ain't That a Kick in the Head.
They Went That-a-Way (25): Complete They Went That-a-Way.
Ring-a-Ding-Ding (25): Complete Ring-a-Ding-Ding.
The House Always Wins (30): Complete The House Always Wins.
For the Republic (30): Complete For the Republic.
Render Unto Caesar (30): Complete Render Unto Caesar.
Wild Card (30): Complete Wild Card.
All or Nothing (15): Complete All or Nothing.
Veni, Vidi, Vici (15): Complete Veni, Vidi, Vici.
Eureka! (15): Complete Eureka!
No Gods, No Masters (15): Complete No Gods, No Masters.
Come Fly With Me (20): Complete Come Fly With Me.
Talent Pool (20): Complete Talent Pool.
Return to Sender (20): Complete Return to Sender.
Arizona Killer (20): Complete Arizona Killer.
You'll Know It When It Happens (20): Complete You'll Know It When It Happens.
G.I. Blues (20): Complete G.I. Blues.
That Lucky Old Sun (20): Complete That Lucky Old Sun.
Volare! (20): Complete Volare!
The Legend of the Star (20): Complete The Legend of the Star.

Dead Money DLC Achievements
Assemble Your Crew (20): Recruit Dean Domino, Christine and Dog.
Cash Out (30): Confront Father Elijah in the Sierra Madre's Vault.
Having a Ball (20): Complete the Sierra Madre Gala Event.
Safety Deposit Box (40): Trap Father Elijah in the Sierra Madre's Vault.
Sierra Souvenir Aficionado (30): Collect 500 Sierra Madre Chips.

Honest Hearts Achievements
In a Foreign Land (20): Scout the Zion Valley for signs of the White Legs.
May my Hand Forget its Skill (40): Evacuate Zion.
O Daughter of Babylon (30): Crush the White Legs.
Restore Our Fortunes (30): Resupply Daniel and the Sorrows.
When We Remembered Zion (20): Arrive at Zion.

Old World Blues Achievements
Cardiac Arrest! (20): Recover X-13 cardiac regulator sneaky suit!
Make Up Your Mind (20): Make up your mind... about your brain.
Making Friends (30): Reactivate all of the Sink's robotic assistants.
Outsmarted (35): Complete Old World Blues.
Spinal-Tapped! (20): Recover X-8 vertebrae-pulse-de-sensitizer frequency!

Lonesome Road Achievements
Complete each achievement to receive the allotted gamerscore.
Condemned to repeat it (20): Decide the fate of all the Divide dwellers.
ED-Ecated (20): Find all of ED-E's upgrades in the Divide.
Hometown Hero (30): Complete Lonesome Road.
Rocket's Red Glare (25): Acquire all upgrades for the Divide's signature weapon.
Warhead Hunter (30): Detonate all of the warheads in the Divide.

Gain higher quality item, than what you paid for
Make sure the vendor has two of the same items, but different quality. If you buy the cheaper quality item; you gain the higher quality item instead

Infinite XP
You need Speech of 30 or the perk Confirmed Bachelor. You must also be on the good side of NCR. Go to HELIOS One and the lady should automatically talk to you. Once she allows you access HELIOS One, you should be able to start the mission "That Lucky Old Sun". Follow the mission and talk to Fantastic and Ignacio Rivas. While talking to Rivas make sure you get him to reveal that he's a Follower of the Apocalypse by using Speech or Confirmed Bachelor and agree with his ideals about peace or just say you're neutral. Do the mission regularly until you get to the point where you activate the Mainframe Terminal. Configure the Power Grid to "5) Full Region (Emergency Output Level). Finish the mission by hitting the Reflector Control Panel outside on top of the tower. Go back to Ignacio Rivas and choose the option "I overloaded the plant. No one.....". The glitch is that the option never disappears, so you can choose to keep pressing it. You get 350XP, 3 Stimpacks, and 2 Doctor's Bag

Infinite XP Glitch
If your speech skill at 50 or higher, you can persuade Old Ben to offer his escort services to the local bar, if you succeed in the Speech Challenge, you'll gain 61 XP. If you follow him back to the bar afterwards and wait until he sits down, you can speak to him again and redo the same Speech Challenge over and over again for infinite XP! You can find Old Ben sitting by a fire close to The King headquarters in Freeside.

Infinite Experience
For this glitch you will need to go to Vault 11 or any other location with mantises. All you need to do is kill a mantis or find a dead one and take the forelegs out of it's inventory. Doing this will give you 22 xp and cause it's body to pop, and If you put the forelegs back in the inventory you will gain an additional 22 xp. You can repeat this multiple times on the same mantis to get the desired amount of xp.

Infinite Caps
First, you must go to the town of Primm. Complete the "My Kind Of Town" quest for them by getting a sheriff for the town. After you get them a sheriff, or the NCR's troops, you have to wait 3-7 in game days, and the Vikki and Vance Casino will open again in Primm. Go there, and exchange some Caps for some of the casino's chips. Then, turn in the casino's chips for caps. You will notice that when you turn the chips in, you don't have them removed from your inventory, however you get the payout. You can exploit this for as long as you want.

Infinite Speech Check Loop
This requires a speech skill of 20. Talk to 10 of Spades in Camp McCarren. You may need to find out about Corporal Betsy's trauma beforehand. Anyway, open a dialogue with him and select "I heard about what happened to Corporal Betsy" then "Tell me what happened." Your next options will be the speech check or "If you were unconscious, how could you have done anything?" Do the speech check, then the other option is the only one available except "Never mind." After you select the unconscious option, the speech check will be available again, but grayed. Regardless, keep pressing A and they'll alternate. Even though the check is gray, it still counts as a pass. NOTE: This does not glitch XP as well.

Set fire to/kill enemies without using ammo!
Equip the Anti Materiel Rifle and load it with Incendiary rounds. Enter vats on any target, then exit vats without shooting them. Whatever you aimed at will now be on fire, with no ammo used.