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.

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

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

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.

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.

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.

This requires that you complete the Wang Dang Atomic Tango quest to perform this glitch. After you complete this quest, Fisto will become an available "escort." First, ask for his services and meet him up in the rented room at the Atomic Wrangler, then use his service. Next, go back to him and talk to him again, but say "Never mind" instead. As a result, he will say "Very well, please return if you require further service," and you will keep getting back 10 caps every time you do this. This works as long as you have the room rented at any time after the first performance, but will not work with the other escorts.

If you fast travel into Scorpion Gulch you will find a wastelander either dead already or about to get attacked by Bark Scorpions. If he is alive pull back as soon as you travel in and watch the Scorpions kill him, now kill them and search the body for a 'Sunset Sarsaparilla Star Bottle Cap'. Fast Travel to Novac and wait 3 days, now fast travel back to the Scorpion Gulch and repeat. This guy always has a star cap on him alive or dead. Repeat till you gain the 50 caps needed for 'The Legend of the star' side quest.

This glitch can be found when arriving at the strip for the first time and you are invited into the Lucky 38 casino, talk with Mr. House and ask about his lifespan (This requires a Medicine check of 35). This will award 35 XP and asking about his age again and reselecting the option 'you appear to be more computer than man will present the medicine check again granting 35 XP each time (This glitch works in the current patched version of the game)

Quick note: You only need 25 Speech Skill to do this. At Camp McCarran, in the Terminal Building, on the ground floor you will find Dr. Hildern. He will give you quest to go to vault 22 accept this quest. Get through this and Angela Williams will come up and speak to you as you're leaving. She will Ask you to save her friend Dr.Keely, again accept this quest. At this point you want to ask her "What's your role here?" followed by "What do you think of Dr. Hildern". You will now have to option to use your speech skill, now simply rise and repeat. You can do this as much as you like, enjoy.

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.