# Infinite XP
When your speech skill is high enough (30 is recommended), go to "Big Town", which is located north of Vault 101. Speak to the girl named Bittercup, and she should tell you about her dating exploits. After speaking with her, go into the house marked "Common House", and speak to a man named Pappy. There should be a speech skill dialogue option that says "You came here with Bittercup, right?" You will get XP every time you click it. Repeat this as many times as desired. Note: This trick works in the unpatched version of the game.
# Easy Caps
Note: This trick requires you take the "evil" path. After agreeing to help Mr. Burke nuke Megaton, go into every single house and steal everything (any little piece of junk you can carry). Sell them to the local shops (Craterside Supplies, The Restaurant, Moriarty's Saloon, etc.). If a particular house is locked or you need a key to get into a safe or something of that nature, just kill the owner of the property, and get the key from his or her body. Kill everyone in sight, especially the shop owners because you can get access to their entire inventory, plus the Caps that you have already spent on them. Kill every one and collect everything to leave Megaton empty. You should have at least 600 caps. Remember to sell some of the things you gather to the shop owners because you cannot fast travel when over encumbered. This can be done in almost any town you visit. To avoid getting over encumbered, get all the supplies that you can possibly carry, then drop the rest just outside of Megaton. Fast travel to Rivet City or some other marketplace. Sell what you have, then return to Megaton, and repeat the process.
# Easy lock picking
Use the following trick to avoid breaking bobby pins when trying to pick a lock. Just before the bobby pin is going to break, exit that screen, then go back. You will save a lot of bobby pins by doing this. This also works when trying to get a password for computers.
# Early detection
When wandering around the world or towns, use the following trick to get an early notification on enemies, encounters, or who is nearby. Keep tapping [V.A.T.S.] while searching at all angles. If there is something out there, you will get the V.A.T.S. zoom in with a low score. You will at least know what is there and can figure out a plan of attack or how best to sneak around it.
# Finding Dogmeat
Dogmeat is found in Scrapyard. On the world map, Scrapyard is in the top right corner of the square that is two squares directly below Minefield. Follow the clear triangle on your compass if you are having problems finding it. Enter Scrapyard, and look/listen for fighting. Your will find Dogmeat fighting a Raider. Once the Raider is dead, you can talk to Dogmeat and ask him to join you.
# Jaeriko
If you talk to Jaeriko about going back into the wastes, he will join you if you give him 1,000 Caps for supply money.
# Getting both rewards in "The Replicated Man" quest
When you discover the identification of the android and are deciding to turn him in or warn him, go to the android first. Convince him to go to Zimmer on his own, and he will reward you. After that, go to Zimmer in the science lab. Tell him about the android's identity. He will also reward you. Note: You will still get bad karma.
# Bobblehead locations
The hidden Vault-Tec Bobbleheads can be found at the following locations. Collect a Bobblehead to gain +10 to a skill or +1 to a stat.