Data Miner

 is an Fallout 3 achievement on Xbox 360 and PC and a trophy on PlayStation 3.

It is granted for hacking 50 terminals.

Locations
Here are some locations of where you will find a high amount of terminals to help towards the Data Miner Achievement. (Please be aware that the computers in the main room, 2 in total, may not be locked if you followed the Blood Ties mission)
 * The Pitt - There is one outside the Supply Plant which will release a veritable army of Protectrons, and three more inside, two which will active a turret grid, and another, a Protectron pod.
 * Vault 87 - There 8 hackable terminals, most are near to where you rescue Fawkes, these are all hard difficulty which will mean you need a Science skill of 75 or higher.
 * Rivet City - There are a total of 7 hackable terminals in Rivet City. Locations: Seagrave Holmes' room, in the Midship Deck. Abraham Washington's room in the Capitol Preservation Society. Bannon's room, in the Upper Deck. Rivet City Clinic, in the Upper Deck. Weatherly Hotel, in the Upper Deck. The remaining two are in the bridge tower on the highest two levels.†
 * Tenpenny Tower - There are 3 terminals (2 Average and 1 Easy) on the Ground floor lobby: one in Boutique Le Chic, which is on the left side of the lobby, one in New Urban Apparel on the right side of the lobby, and one in Federalist Lounge, also on the lobby's right side.†
 * Underworld - 4 Terminals (3 Very Easy, 1 Average): Tulip's Terminal, located on a counter inside Underworld Outfitters, which is on the left side of the bottom floor, Winthrop's Terminal, located in the room to the right of The Chop Shop, a research terminal, located inside The Chop Shop, and Ahzrukhal's Terminal, located atop the counter in The Ninth Circle.†
 * Megaton - 5 Terminals: Children of Atom, Craterside Supply, Moriarty's Saloon, The Brass Lantern and the Megaton Armory.†
 * Meresti Trainyard- 5 Terminals: The First terminal can be found just after you pass the guard,and is on the left hand side. The second is inside the vampire hideout in the bottom left of the room. The Third is on the right of the room, next to the work bench. The fourth is upstairs next to the cell where Ian West was held during the mission Blood Ties. The fifth is Vance's terminal, and can be found upstairs in the room on the left hand side before the turnstiles.†
 * The Citadel - There are 3 terminals in the B-Wing, none of which result in karma loss. (The Clinic, Squire Maxons Room and Elder Lyons' room)
 * Arlington Library - There are 4 hackable Terminals. One is in the lobby (easy). The other three are in the Arlington Library Media Archive. One in the middle floor and the other two on the top floor. (Average)
 * Germantown Police HQ - 4 Terminals. Two on the Ground floor, the other two are on the top floor.
 * Fort Bannister - 3 Terminals. One in the bunker and two in the Commanding Officer's Quarters.
 * Enclave camps usually have hackable terminals that give info about Enclave missions as well as options to power down defense grids.
 * If you're feeling like a prankster, you can hack the turret control terminal out in front of Fort Independence, which is in the ground next to the basement door, under the bridge. Also there are many other terminals throughout Fort Independence.†
 * The terminals in Our Lady of Hope Hospital are on the first floor allowing you get obtain various medical supplies.
 * Nuka-Cola Plant: Inside the factory to activate the convoy, which is used to get three Nuka-Cola Quantum for the quest, The Nuka-Cola Challenge.
 * Grayditch - One in the Brandice's House and another in Doctor Lesko's Shack (Easy and Average).
 * Paradise Falls - In Eulogy's Pad, on the table with the Speech Bobblehead near the heart bed. (Average)
 * Vault-Tec Headquarters: 3 terminals to unlock then unlock master computer. (also download info onto pip-boy where vaults are located)
 * Super-Duper Mart has a terminal (Easy) to the rear of the building. Which unlocks a door and leads to another terminal (Average) along with 3 Nuka-Cola Quantum's and good loot.
 * Old Olney Sewer has a Terminal that releases a utility protectron

† Warning: You will lose Karma for hacking some/all of these terminals.