Fallout: New Vegas

This glitch requires a 20 Speech skill level. Talk to the 10 of Spades in Camp McCarren. You may first need to find out about Corporal Betsy's trauma. Start a dialogue with him, and select "I heard about what happened to Corporal Betsy", then "Tell me what happened". The next options will be the Speech Check or "If you were unconscious, how could you have done anything?" Do the Speech Check, and then the other option will be the only one available except "Never mind". After you select the unconscious option, the Speech Check will be available again, but grayed out. However, you can still keep pressing A, and they will alternate. Even though the Speech Check is grayed out, it still counts as a pass.

Pick up an item by clicking the Right Analog-stick. You can then drag it anywhere desired (like out of the eyesight of the shopkeeper), and press A to add it to your inventory.

Use the .50 machine gun incendiary ammunition on the anti-materiel rifle. Target an enemy with V.A.T.S. The enemy will catch on fire, even if you do not fire the weapon.

You can locate the field "gun" for the ARCHIMEDES weapon by entering the Freeside's East Gate and locating the two children chasing each other (not chasing the mutated rat) during daylight. Talk to the one possessing what appears to be a toy gun. You can purchase the gun for 1,000 caps or 20 caps with Barter at level 45 or greater. To use the weapon you must supply the power to ARCHIMEDES II during the "That Lucky Old Sun" mission.

By using this method, it is possible to repair any and all items to the player's current repair level without using any of you caps. To do this you, need the Confirmed Bachelor perk and enough caps to cover the repair cost of the item. When you arrive at the Mohave Outpost to get the pardon for the new sheriff of Primm, during the conversation with Major Knight a Confirmed Bachelor speech option is available. Select it, and whenever you do repairs through him, the item gets repaired to your repair level but the caps do not get deducted from your stockpile. This can be very useful when combined with any unlimited caps trick, and results in your player having all items at 100% condition (even things like the Fat Man, where replacement parts are difficult to find).

Find a vendor that has two of the same items, but different quality. If you buy the cheaper quality item, you will still get the higher quality item.

Search the indicated locations to find all seven Snow Globes:

Goodsprings: In Goodsprings Cemetery, at the foot of the small rectangular gravestone, near where the earth has been dug up, close to the water tower.
Mormon Fort: In Old Mormon Fort, inside the same tower as Julie Farkas' office, on top of a wooden bookcase.
Test Site: In Lucky 38 Casino, in the cocktail lounge, on the curved sideboard across from the entrance, behind the till.
The Strip: In Vault 21, inside Sarah's locked bedroom, between the two beds, on a small table.
Nellis AFB: In Nellis Air Force Base, inside Pete's museum, on the corner table by the mural.
Hoover Dam: In Hoover Dam, on a desk in the visitor's center, by a terminal.
Mt. Charleston: In Jacobstown, on the large curved desk in the reception area of the lodge, near the terminals.

Search the indicated locations to find all Hollow Rocks, which contain ammunition and equipment stashes:

1. Northern Passage: On the eastern rock wall, near the grave and "The Sun Is Killing Me" graffiti.
2. Ruby Hill Mine: Part of the rock wall, just to the right of the door.
3. Charleston Cave: Part of the rock wall, just to the right of the door, by the heart graffiti.
4. Silver Peak Mine: Part of the wall, just to the right of the shack through which you enter.
5. Vault 22: On the north bank, across from the "Keep Out" sign, by the entrance.
6. Jacobstown: Just outside the perimeter, to the right of the main entrance, where the Super Mutants stand guard.
7. Remnants Bunker: About 10 feet north of the entrance, part of the rock wall.
8. Chance's Map: Adjacent to the dirt map, with "The Sun Is Killing Me" graffiti on it.
9. Bloodborne Cave: Just to the right of the cave entrance.
10. Cannibal Johnson’s Cave: Just to the right of the cave entrance.
11. Fisherman’s Pride Shack: By the campfire, north-west of the shack.
12. Camp Guardian: Next to the Camp Guardian population sign, at the base of the path up to Guardian Peak.
13. Follower’s Outpost: Built into the steps of the signal box structure.
14. Boulder Beach Campground: By the side of the road, north-west of the jetties, with "The Sun Is Killing Me" graffiti.
15. Cazador Nest: Part of the rock wall, on the east side of the nest alcove, facing back towards the alcove.
16. Tribal Village: At the start of the Ravine Path, close to the corpses and tents.
17. Makeshift Great Kahn Camp: On the west side of camp, near the desert plants.
18. Yangtze Memorial: At the base of the south steps, with the peace symbol graffiti.
19. Goodsprings Cave: Just to the right of the cave entrance.
20. Primm: Attached to a large rock, near the scattered chems and the rock perimeter, above the concrete support wall.
21. Jack Rabbit Springs: South of the pools of radiation, on the shore of the Dry Lake.
22. Morning Star Cavern: By the entrance to the cavern, by the bones and the explosive crate.
23. Crescent Canyon West: In the canyon, on the west exit slope, adjacent to a rusting car husk.
24. Crescent Canyon East: On the east exist slope, just after the rail bridge.
25. Vault 11: Just to the right of the entrance.
26. Black Rock Cave: Just to the north of the fallen radar dish.
27. El Dorado Dry Lake: West of the Savaged Brahmin, in the sands of the Dry Lake.
28. Hidden Valley: West of the eastern bunker, with the "no missile" and heart graffiti.
29. Powder Ganger Camp East: Next to a Honey Mesquite Tree, around 20 to 30 feet south of the camp.
30. Primm Pass: Close to the Brahmin bones, on the western end of the pass.
31. Dead Wind Cavern: On the south rock wall slope, around 20 to 30 feet from the entrance.
32. Hidden Supply Cave: To the left of the cave entrance, with the "no missile" graffiti.
33. Walking Box Cavern: Around 20 to 30 feet east of the cavern entrance.
34. Broc Flower Cave: At the foot of the entrance slope, with "The Sun Is Killing Me" graffiti.
35. Abandoned BoS Bunker: With the small cluster of rocks and shale on the slope leading up to the bunker grating.
36. Techatticup Mine: To the right of the entrance, with the white blocks graffiti.
37. Lucky Jim Mine: Slightly beyond the shack, near the wooden cart.
38. Searchlight North Gold Mine: On the flat rock bank to the south of the entrance hole.
39. Searchlight East Gold Mine: Southeast of the entrance; climb on the pile of rock and shale to reach it.
40. Cottonwood Cave: On the road between the two sets of crucifixion poles, with "The Sun Is Killing Me" graffiti.
41. Bradley's Shack: On the west side of the entrance, by the small valley landslide.
42. Fire Root Cavern: At the foot of the entrance slope, on the left.

Unlock Xbox Live Gamerscore points, by completing the following Achievements.

Go south on the road out of Goodsprings. After about 100 yards you will find a refrigerator at the base of a hill. There is a skeleton wearing a fedora inside.