Best memory was getting my SNES. It was my first console, and I still consider it to be the best console ever made.

Just a few that stand out:

My dad brought home the preview edition of Deus Ex. I could basically play up to the point where *SPOILER* JC leaves for Hong Kong *SPOILER END*. I love every minute of it. I played that preview edition probably six times. Much later, I purchased the full game from Amazon. I played it and loved it. But it wasn't until I played it again that I really, really loved it. I took it slow. I moved through the game at a slow pace. I found areas I hadn't found before. I did things I hadn't done before. It was just a great experience.

My third playthrough of Bioshock was similar. I took it incredibly slow, and I played on Medium difficulty (I had played on Easy the previous two times). It was an awesome experience.

The entirety of Cryostasis' story has stuck with me ever since I beat over a year ago. I haven't played it since, but I still think about it quite often.

The opening section of Uru has stuck with me for a long time. Something about starting out in the middle of a desert with no context and no immediately apparent goal was incredible--never before had I played a game that didn't give me an obvious clue about what I was supposed to do.

*MASS EFFECT 1 SPOILERS AHEAD* Never before had I played a game quite like Mass Effect. I'd played Knights of the Old Republic, sure, but Mass Effect was different somehow. I had a lot of fun. But it wasn't until close to the end of the game that I experienced one of only a few game-related jaw-dropping moments. I was trying to stop Saren from doing whatever he was doing and, having maxed out my Charm skill, I chose the Charm dialogue option. Imagine my surprise when Saren, influenced by the choice I had made, shot himself in the head. *END MASS EFFECT SPOILERS*

The final moments of Final Fantasy XIII have stuck with me. I've read in some places where people have called the ending a little cheesy--maybe they're right. But it was very impacting to me. I got the game in my last year of high school, so with being at school all day and then having to do homework in the evenings, I didn't have a lot of time to play. It took me a little over a month to beat it. Playing it for such a long time, the ending seemed like an epic conclusion to what had been (to me, at least) an epic game. When the credits finished rolling, I felt this incredible sense of accomplishment.

*SPOILERS for the game HEAVY RAIN*
-Breaking into the apartment of a man who is an alleged drug dealer and, after getting into a heated fight, pulling out a gun and killing him while yelling 'I'm a father, too!'. That was gut wrenching to watch.
-Chopping off your finger in the trials in Heavy Rain to save your son. Just forcing yourself to do it hard enough let alone watch such realistic reactions to it.

"You are standing in an open field west of a white house, with a boarded front door. There is a small mailbox here."

Okay, that does sound pretty awesome.

In a way, the beginning of System Shock and ICO rubbed me the right way in the beginning. First you "wake up" in an unfamiliar place not knowing what to and where to go, then pretty soon your complete loneliness is broken when you make one single contact to another living being (in ICO's case you even lack the ability to communicate clearly because you are speaking Japanese and the white lady is talking some gibberish, probably Korean or something :)).

But I'm pretty sure that setting has been quite overused already in more modern games.

EDIT: Oh yeah and I participated in this thread already in 2011...

For some reason I have this really vivid (and nostalgic) memory of the first Syphon Filter, especially the first level with the guys in yellow hazmat suits, and also the subway mission after that. In fact now that I consider it most of my earliest gaming memories were from the PS1... I must admit.

Anyone here remember the mission editor/map builder for Tenchu 2: Stealth Asssassins? Oh man, fun times.

Another month-long bump, to see if anyone else wanted to share.

Went round a mates house to play on his super-powerful 386 - just sat and watched him play Civilization for about 4 hours, and still consider it to have been time well spent...

Shadow of the Colossus
Had a couple of friends over, I had just defeated the fifteenth colossus and was on my way to face Malus, the sixteenth and final one. Ride out to the sealed door, reflect the light with my sword just right to unlock the door, as the cutscene of it opening plays, with the light shining through and the music making it a glorious moment, the power goes out!
My friends and I look at each other quietly for a second and just explode with laughter. The timing of that moment was so damn perfect, it was incredible.

Grand Theft Auto: Vice City
This was on the PC version and I regret not thinking to get a screenshot.
That part where you meet Lance, during the cutscene where you're pulling up to your hotel, Lance somehow ended up on a moped!
The thing about it is he only goes straight to his car and you can't switch because he doesn't get out with you, so you have to drive that car and yet somehow...
It was hilarious cause seeing someone say "I'll be watching you..." then driving off into the night on a moped is probably the least badass way to make an exit.

Fallout
So I'm wandering the wasteland as I do, I'm around the Lost Hills when suddenly random encounter time!
Pack of bandits getting ready to take on some paladins, yada yada yada, place is littered with bodies cut in half from minigun fire and the paladins are just walking around like they own the place...cause they do.
That game was filled with all kinds of great moments.
"Moo, I say!"

My goodness, I loved that game!

Had all kinds of fun with the taser...

Duking it out against Anton Girduex...

One of my favorite levels is the Pharcom Warehouse, love how chaotic the action was in that one. Even as you're arriving you hear that massive, ongoing explosion of gunfire, all you can think is "things are about to get so serious, it'll be uterlly silly."

I know what you mean about Georgia Street and the subway, that's usually what comes to mind when I think of Syphon Filter.
"Copy, I'm on my way."

Did you play #2?
Lian Xing, Club 32 in Moscow, that level was so damn cool. When that music starts, it just goes off!

Plus the death screams for the taser were so hilarious and they added that charring effect, I like my terrorists well done.

In Diablo 2 , when i made my first LVL 99 HC char. It was a summoner necro, and i LVLed killing Baal on hell... I even remember what i had for breakfast that fine day june 9th 2003...

That's when you know it was a truly amazing day.

Playing Oblivion for the first time (my first Bethesda game) and coming out of the sewers into the light and looking out at the huge world.

I loved that moment. I was playing the game and my girlfriend (now my wife) was watching. She'd never spent time around video games before and I could all but hear her mouth hit the floor when she saw how beautiful a game could be. Last fall, I swear she was more excited to get Skyrim than I was (and I waited outside in the cold for three hours to get my pre-order copy).

My favorite moment though has to be the ending of the Witcher.

SPOILERS...
When I realized that Alvin was my enemy, it broke my heart. Maybe I'm a dreamer, but I was hoping that Geralt might be able to have a normal life after it was over, with Triss and Alvin as a kind of surrogate family. I was wrong, and it made me sad all night.
END SPOILERS

I've played hundreds of games in my life, and for some reason that was what resonated with me the most.

*** Spoiler Alert ***

If you have not played EOB1 or EOB2


There are so many as each game has something. I am going with a couple old favorites: EOB and EOB2 (Thanks Westwood). The first time I used the stone portal in EOB1 was absolutely amazing. The apprehension of the unknown and the sound effects coupled with headphones late at night - memorable. EOB2 - Dran Dragore turning into a Dragon after I had killed him and thought I had won the game (ouch).