HT Games
Broken Steel
The "Broken Steel" add-on to "Fallout 3" is included with the Game of the Year Edition and picks up where the main story of "Fallout 3" left off. Your character wakes up in the Citadel completely healed, and you must embark on a quest to finish the fight against the Enclave or destroy the Brotherhood of Steel. This add-on also includes a new weapon, the Tesla Cannon, which fires a massive burst of electrical energy and kills most enemies with a single shot.
Operation Anchorage
This add-on does nothing to advance the storyline of "Fallout 3," but gives you a new mission with some Brotherhood Outcasts. You must enter the simulation of Anchorage created to train soldiers in order to free Alaska from invading Chinese armies. Completing the mission in this add-on rewards you with new weapons, armor and a Perk. The Perk, called Covert Ops, boosts your Lockpick, Science and Small Guns skills. You also get a Gauss Rifle, Chinese Stealth Armor, a Shock Sword and T-51b Winterized Power Armor.
The Pitt
"The Pitt" sends you to Pittsburgh, which has been turned into a slave colony -- like a larger-scale Paradise Falls. There, you must find a cure for a disease spreading across the country. Pittsburgh is an entirely new area in "Fallout 3," with new characters, missions and equipment. Most notable among the new weapons is the Auto-Axe, a powered axe delivering deadly melee attacks.
Point Lookout
As with "The Pitt" and "Operation Anchorage," "Point Lookout" does not add anything to the main storyline. Instead, it takes you to a new area just outside of the Capital Wasteland to Point Lookout, a national monument. You can complete up to five new side-quests rewarding you with new equipment, such as the Bio-Gas Canister, Double-Barrel Shotgun, Fertilizer Shovel and Microwave Emitter.
Mothership Zeta
If you managed to find the crashed Alien Ship and log the Alien Distress Signal into your Pip-Boy, you know aliens must have something to do with the "Fallout 3" universe. The "Mothership Zeta" add-on takes you aboard an alien spacecraft from which you ultimately must escape due to the hostility of your otherworldly captors. "Mothership Zeta" adds a cache of new alien technology to your arsenal, including weapons like the Shock Baton, Drone Cannon, Alien Atomizer and the MPLX Novasurge, a unique Plasma Pistol.