First game I thought of:
Breath of Fire IV
This is probably my favorite JRPG. It's a combination of things: I like the graphics, music, characters and battles with a great combo system and plenty of skills. In a word, I'd say it's the overall atmosphere. The game has it's weaknesses, but something in it always just resonates with me. It's a joyous day if this is ever released on GOG.

Honorable mention:
Vampire: The Masquerade - Bloodlines
I really liked this game because oh you know why.

Seconded Bloodlines! If i could choose another one, that totally would be it! However buggy and flawed it is still.

There are many games that I hold close to my heart but I'll say only one (because if I start making lists now, I'll finish them tomorrow and I'll only manage to list my favourite cRPGs by that time!): "Grand Prix Legends"

I've put countless hours in this marvelous racing simulation and I'm still going strong.. Be it for the hundreds of tracks, be it for the wonderful F1s of that age, I don't know but this is my favourite game.

Same for me. I had been away from gaming for a long time, and this was my introduction back into it (last game I played was diablo 2). I'd never done an open world game before, and I was completely mesmerized!

My top 3:

Star Wars: X-Wing vs. TIE Fighter: No story? So what? The brain-numbing fun of being able to fly an X-Wing in the first SW sim I owned will always bring a smile to my face and fueled a passion that's led to me acquiring most of the SW PC games.

The Complete Ultima VII: Traveling around as the Avatar and getting sucked into this story were important parts in my formative years as a PC gamer. The third-party Exult program makes it even better.

Star Trek: Armada: I've yet to find any RTS I've enjoyed as much as this. Finding ways to make it work on newer systems (it won't work on 64-bit OSes at all) always ends up being worth it in the end. It also spawned numerous community mods that enhanced its replayability.

Five games that have been special to me, for different reasons.

Civilization (the original CIV.EXE): It actually helped me to understand some patterns that are repeated in real history. This is my game (along with its sequels, Civ2, etcetera, up to the very gamey CIV5, and without forgetting the stupendous Alpha Centauri).

King of Dragon Pass: An amazing experience, this game endures the test of time. It has everything: roleplay, generations, war, lore, you name it.

TIE Fighter: It made you a pilot.

Botanicula: A game that somehow manages to make you happy. We need more like this.

Exile: There was a time when games like this were fashionable. I enjoyed it more than the sequel Avernum (that reduced the party from 6 to 4).

Zero Tolerance - SEGA Genesis
A very underrated space FPS with tons of levels and action. It sadly got buried during the Doom revolution, but was otherwise a really good shooter. Still remember the sounds and and images. The elevators that moved you between levels even had elevator music... thought that was a nice touch.

Berzerk - Atari 2600
One of the first video games I ever played. Was one of the most fun as well. Never felt so much fear from an attacking smiley face (good old Otto).

Quake definitely was a great game! I still remember when I first played it and I was amazed by the great graphics and gameplay! It was the first FPS to have truly 3D graphics and it didn't rely on sprites like Doom. I just wish they hadn't gone the "Doom-clone" route with Quake 2.

The game dearest to my heart? Hmm... i'd have to say NwN 1. Spent 9-10 years playing on various servers and it was the reason i learned about roleplaying. Got many good memories from that time.

Honourable mentions: Civilizations II and The Settlers. I'd mention the original Civilization too, except it wasn't before Civ II i really understood and got good at the game. I was too young when i played the original to fully get into it (although i remember watching my grandfather play it and he was pretty good at it).

And while the three following sequels to the Settlers was much, much better than the original. There is just a certain charm about the first one. I still remember watching that first Settlers intro. So much nostalgia. <3

Yes. It is set in the [url=http://whitewolf.wikia.com/wiki/Vampire:_The_Masquerade]World of Darkness setting.[/url]

You certainly have touched on a complicated topic. As many have stated, it depends on what they are playing for at the time, or when they would be asked.

For me, one of the first games that made a truly deep impression and got close to my heart was Thief: The Metal Age. Thief Gold was good, but I got sick of the sheer volume of undead levels. I much more enjoyed sneaking around living people and snatching stuff from under their noses!

Deus Ex is also pretty high on the list, and I cannot wait for Revision to come out so I can see what they have done.

The rest would be dependant on genre.
FPS:
Blood and Shadow Warrior (original) both stole and gave me many hours of my life.
Bioshock Infinite is there too, for the sheer wonder of the environment.

Isometric RPG:
Fallout 1 and 2, and Wasteland 2.
I do like the real time combat games like NWN and all, but I love turn based games.

First Person RPG:
Fallout 3
I like the other offers, like the elder Scrolls series, but I never finished them. FO3 captured me till the end.

Sneakers:
Dishonored
Thief
Deus Ex: Human Revolution
Yes these can be played in more than one style, but if given the choice then I will always go for the no kill approach if possible.

On my playlist that I am really enjoying right now:
Hard Reset
Terraria
Neverwinter Nights 2 (dagnammit, imma gonna finish it this time!)

But, the number one game that made the deepest impression of all was Betrayal at Krondor. It gave me my love of turn based strategy, role playing, exploration and introduced me to Midkemia all in one package. I would love to see a remake, though as long as the rights to the IP are tied up in legal purgatory that will never happen. Just as long as any potential sequel or reboot doesn't end up being the waste of coding time that Return to Krondor was.


Of course, if I was to answer this post tomorrow then any or all of these games might change!

Hm quite a few. But the first one was probably the Marathon Trilogy by Bungie. They were basically just shooters (although a bit more technically advanced and with more complex gameplay than Doom which was essentially around the same time).

They had a really detailed, partially crazy science fiction story, a huge amount of lore and very memorably (and funny) villains and allies, although alliances tended to be fragile at times, all communicated through text.

Add weapons with alternate fire modes, level aims that didn't just consist of "find the red key", vacuum and low gravity levels and huge amounts of mods and even TCs for that time. Even made a whole bunch of levels myself back then.

Oh multiplayer modes were also a lot more fun than standard deathmatch back then.

One of the most memorable levels was one with an underground mining facility (or something) of the enemies, the mission was to destroy it, so you go in and destroy two terminals and suddenly the lava in the level started to rise and you had to run all the way up while the mine got completely flooded. After that you essentially discover the second part of the map which was flooded before. What a great idea and a hasty run up those stairs :D Awesome game...

Other games that impressed me:
Deus Ex
Stalker Series
Bishock Infinite (although the gameplay was a lot better in the previous instalments)
Baldurs Gate and Planescape Torment
Mass Effect series (i never got why people disliked the ending)

Command & Conquer: Renegade.
I love it not just because its a great game (its an awesome FPS with awesome gameplay) but I also love it because I am so heavily involved with the mod community for the game and have written (or reverse-engineered from the game code) thousands of lines of code for it (I probably know more about the internals of this engine than anyone else on the planet except possibly its original creators but even they probably dont remember a lot about a game this old that they likely haven't touched in a decade or more)

Command & Conquer Tiberian Dawn.
This was the game that did more than any other to kindle my love of pulling games apart and seeing what made them tick. It was also one of the first games I ever got seriously into modding of.

Pipes.
Old game I wrote in Visual Basic with help from my father (who was the person most responsible for getting me into computer programming) that never really got released anywhere. As the name implies its one of those "join the pipes" games where you join different bits of pipe to connect the in pipe to the out pipe. Wasn't that good (for example the water flow just rose from the bottom of the screen to the top of the screen rather than actually flowing through the pipes). But the memories attached to it...

World Tour Golf (old CGA golf game).
First game I ever remember playing that had any kind of user-generated-content and I have yet to see any other golf game that lets you create your own courses.

[Edited due to complications from obsessive-compulsive disorder. My apologies. Please move along.]

I guess i'm in the minority where it doesn't change depending on what games i'm playing. NwN, Civ II and Settlers will always have a special spot in my heart. I'd love to play Settlers 1 again just to relive the nostalgia, so i'm hoping it will come to gog sometime in the future.

Goodluck with that. :) Took me untill the third try to get through the main campaign. Still haven't completed Storm of Zehir yet even though i liked that one better than the other two campaigns. Mostly because i got distracted with other games.