Fallout 3 PC Game Cheats

Cheats:
When playing hit the tilde (~) key to pull up cheat console.

Input addspecialpoints X - Special Points (X = amount)
Input addtagskills X - Tag Skill Points (X = amount)
Input advlevel - Level up
Input GetQuestCompleted - Finish present quest
Input getXPfornextlevel - Up one level
Input help - Display all console commands
Input modpca Y X - S.P.E.C.I.A.L. stats (Y = stat type, X = amount)
Input modpcs Y X - Skills (Y = stat type, X = amount)
Input player.setlevel X - Set player level (X = level)
Input player.additem 000000F X - Get indicated amount of caps (X = amount)
Input removefromallfactions - Remove player from all factions
Input rewardKarma X - Add indicated amount of Karma Points (X = amount)
Input setpccanusepowerarmor X - Toggle Power Armor use (X = 0 or 1)
Input setspecialpoints X - Set Special Points (X = amount)
Input settagskills X - Sets Tag Skill Points (X = amount)
Input tcl - No clipping mode
Input tmm1 - All mapmarkers
Input tdt - Toggle debug display
Input tlv - Toggle leaves
Input tgm - God mode

V.A.T.S.:
To survey the area around you for foes you missed, hit the VATS button repeatedly as you make your character spin.

Continuous Hacking:
You have 4 attempts to hack successfully. Try 3 times, bail out, then try again; repeat this process.

More Space:
When running out of inventory space, find a companion character to help you.

Achievements:
Vault 101 Citizenship Award (10GP) - Acquire the Pip-Boy 3000
G.O.A.T. (10GP) - Acquire the G.O.A.T.
Escapee (20GP) - Finish "Escape!"
Following (20GP) - Finish "Following in His Footsteps"
Galaxy News Radio (20GP) - Finish "Galaxy News Radio"
Science (20GP) - Finish "Scientific Pursuits"
Tranquil (20GP) - Finish "Tranquility Lane"
Waters of Life (20GP) - Finish "The Waters of Life"
Trail (20GP) - Finish "Picking up the Trail"
Paradise (20GP) - Finish "Rescue from Paradise"
Garden of Eden (20GP) - Finish "Finding the Garden of Eden"
American Dream (20GP) - Finish "The American Dream"
Take it Back (40GB) - Finish "Take it Back!"
Big Trouble (20GP) - Finish "Big Trouble in Big Town"
Superhuman Gambit (20GP) - Finish "The Superhuman Gambit"
Wasteland Survival Guide (20GP) - Finish "The Wasteland Survival Guide"
Those (20GP) - Finish "Those!"
Nuka-Cola Challenge (20GP) - Finish "The Nuka-Cola Challenge"
Head of State (20GP) - Finish "Head of State"
Replicated Man (20GP) - Finish "The Replicated Man"
Blood Ties (20GP) - Finish "Blood Ties"
Oasis (20GP) - Finish "Oasis"
Power of the Atom (20GP) - Finish "The Power of the Atom"
Tenpenny Tower (20GP) - Finish "Tenpenny Tower"
Business (20GP) - Finish "Strictly Business"
Shoot 'Em in the Head (20GP) - Finish "You Gotta Shoot 'Em in the Head"
Stealing Independence (20GP) - Finish "Stealing Independence"
Homefront (20GP) - Finish "Trouble on the Homefront"
Agatha's Song (20GP) - Finish "Agatha's Song"
Reilly's Rangers (20GP) - Finish "Reilly's Rangers"
Reaver (10GP) - Get to Level 8 with Bad Karma
Mercenary (10GP) - Get to Level 8 with Neutral Karma
Protector (10GP) - Get to Level 8 with Good Karma
War Harbinger (20GP) - Get to Level 14 with Bad Karma
Pinnacle of Survival (20GP) - Get to Level 14 with Neutral Karma
Ambassador of Peace (20GP) - Get to Level 14 with Good Karma
Scourge of Humanity (30GP) - Get Level 20 with Bad Karma
Paradigm of Humanity (30GP) - Get to Level 20 with Neutral Karma
Last, Best Hope of Humanity (30GP) - Get to Level 20 with Good Karma
Weaponsmith (30GP) - Have one of every custom weapon
Bad Playmate (20GP) - Slay 300 people
Beast Slayer (20GP) - Slay 300 creatures
Good Speaker (20GP) - Prevail in 50 Speech Challenges
Data Groker (20GP) - Hack into 50 terminals
Keys are for Cowards (20GP) - Pick 50 locks
Scouting Party (20GP) - Find 100 locations
Prankster (10GP) - Drop a grenade or mine while pickpocketing
Harder they Fall (20GP) - Slay all the Super Mutant Behemoths
Dolls (10GP) - Get 10 Vault-Tec Bobbleheads
Vault-Tec C.E.O. (30GP) - Get 20 Vault-Tec Bobbleheads

Behemoth Locations:
Can be located in: Evergreen Mills, Galaxy News Radio, Jury Station, Takoma Industrial, and The Capitol Building.

Locating Dogmeat:
Go to the Scrapyard, northeast from Megaton, over the river, where you'll find the dog.

Unlimited Good Karma:
Outside the towns of Rivet City and Megaton, you can locate parched people who ask you for filtered water; give them it to increase your karma.

Avoid Breaking Bobby Pins:
Be patient when picking locks; after a 3rd attempt, the pin may break, so back out after the 2nd try and go back to reset the pin strength.

Increasing Your Experience:
Set the game's difficulty to Very Hard; next, hack the computer or do some lock picking. These actions will give you more experience points.

Stowing Goods on Dead Bodies:
Place your own goods onto a corpse and get them later.

Infinite Mutant Karma:
Go to Big Town at night; The town will be attacked from a Super Mutant raiding party; slay each Super Mutant to acquire more karma.

Conserve Your AP:
When battling a foe or group of foes, aim at them in VATS, but don't shoot. You'll keep your AP but still be aiming at the part of the foe's body you were in VATS.