OK, this thread just for moments that you remember from playing any Fallout games. Now, this isn't your favorite moment, but just moment(s) that you remember for various reasons. Here are a few of mine to use as an example.
Fallout 3: The first Fat Man I ever found was at the Super-Duper Mart wielded by a Raider. Somehow I was only injured by the other Raider who had a hunting rifle.
Fallout New Vegas: During my first play through of New Vegas I decided to go up north of Goodsprings only because the signs said not to. I was then mobbed by Cazadors, thus causing me to eternally hate them, and eventually returning with Cleansing Flame loaded with optimized flamer fuel and killed the shit out of every single one of them.
New Vegas: After killing all the Legion soldiers in the Fort, I went into Caesars tent, killed everyone WITH CHANCES KNIFE!!!, dragged all the bodies and parts over to his throne, sat down, and took this screenshot.

Sparing with a Deathclaw with my Legion Female Courier. Then killing Ulysses with nothing but my bare hands.

Letting President Eden live and infecting the water supply. Ahh, good times.

Oh easy. This had be laughing for a little while. Just something I noticed in Big MT.

Hhhmmmmm........ Saving the NCR hostages at camp Nelson with Boone at my side. That ranger said it couldn't be done.
Shooting Ceasar in the face after he went on a rant when I told him I wasn't working for him when I was done activating the securitron army.
...... Yeah, Darren doesn't like being told what he can/can't do.

Oh i have a great one from 3
I'd just compleated operation anchorage for the millionth time and decided to clean out the Superduper mart.
Well guess what, one of the raiders found the freaking firelance and killed me...
I've never found the gun again

As for Vegas i've got to say it was the first time i found aliens with the wild wasteland perk, it was just so unexpected that a burst out laughing

Fallout 3: The first encounter with a Super Mutant Behemoth at GNR.

New Vegas: Storming The Fort with a full-auto rocket launcher.

Go to Outcast Outpost with full suit of Outcast Armor, and the defenders thought I was one of them.(This and the slave outfit in The Pitt is probably the inspiration of the disguise system in NV.)

Also, General Jingwei's horrible Chinese.(I'm a Chinese myself, and I can barely understand him without the subtitles.)

New Vegas: getting the gra anti-material rifle and killing the shit out of everything with explosive rounds.

New Vegas: dismissing my companions, giving myself only a bat (and I hadn't leveled up Melee) and killing every fiend in Vault 3.
Fallout 3: Operation Anchorage. I would always get only the sergeant guy and all the soldiers, and then set it to expert so I can watch the gruesome deaths.

3: Has to be when I found the Experimental MIRV. I literally ended the world a second time.
3: Blowing up megaton, because nuclear explosions fuck everything up beautifully.
New Vegas: Getting the unending shit kicked out of me by Lanius, then later shoving a Holy Frag grenade up his ass on a later playthrough. I serve vengeance cold with a slice of Irony.
New Vegas: The ending of Lonesome Road, By far the only video game ending thingy where I actually felt my actions changed the game.

I'm a terrible bastard in the game sometimes.

480072Where do you find the MIRV?

480180 National guard Depot, north or DC.

Escaping Vault 101. I've just replayed the intro endlessly so many times...

Shoot out with the powder gangers in Goodsprings. I felt like a spaghetti western hero.

And then there's throwing Oliver from the dam.

Fallout 3: The first enclave I ever found being killed by a molerat while fawkes sledged a wall
New Vegas: Going into the fort alone at level 3 in hardcore mode, reverse pickpocketing a frag mine into one of Caesar's guards, looting a ballistic fist, and killing everything in the fort. Glorious memories.
New Vegas: Dropping the radioactive barrels onto Cottonwood Cove and realizing that I had killed the slaves

480180
You'll need all the Keller family transcript for that.
http://fallout.wikia.com/wiki/Keller_Family_Refuge

I shot a fiend and he flew into a telephone pole, stretching around it like a rubber band before flinging into the air and spazzing out violently, limbs ranging from two milimeters long to two miles long within a nanosecond.

Then he teleported inside me and I died.

I had angered the fallout gods on that day.

484286
Ah, the curse of the Railway Rifle.

484791 This was in New Vegas.

484852
Oh.
Well, something similar happened to me in 3.
And in New Vegas, too. Crossbow mods are fun!