For me, it was the game Rocket Jockey released by Sega Soft in '96. It was perfect. The game featured a surf rock soundtrack by Dick Dale. The entire premise of the game was to ride around on rockets and using long cables to yank your opponents off theirs. Referees were also fair play. I don't think I've met anyone else who has played the game, so if you have, let me know!
I was totally sucked into the world when I first played it as a kid. The balance and trade offs between tech and magic are awesome and the incredible dialogue and (OK from what I remember) story makes this one I come back to every once in a while.
I don't think I ever actually have beaten the game though -- but I do that with nearly every game.
I played the shit out of Rocket Jockey. We only played it once together at a Lan party because I kept tying my friends together. Fun for me, not for them!
I was a big LucasArts graphic adventure game fan.
Maniac mansion, Zak McKracken, Indiana Jones, Loom, Monkey Island
Then all the Sierra games:
leisure Suits Larry, Police Quest, King’s Quest, Camelot….
Good times.
I really loved Tie Fighter from 1994. The music was pretty cool because it changed based on the state of the mission you were on and star wars music was a cheat code to my feelings.
I also thought it was so cool when you'd complete secret objectives and they'd bring you in to the emperor's secret order and tattoo your arm. I thought that was just fucking great. Those cut scenes were so cool.
Also thanks to all of you who posted cool older games im going to try some of these. I'm thinking about trying fallout I've never played any in that series.
Rebel Assault 1 and 2 -- they're total crap, but if you were a Star Wars fan at the time, they were epic. FMV in RA2 was so good, and introduced story unique to the game.
Descent is really hard to beat for me. I put it above Doom/Quake in terms of actual gameplay. It felt so nice to rush to the exit when you're really good. Only Majora's Mask 3-days mechanic has rivaled the anxiety factor of Descent.
Releasing the T. rex and plopping guests into the shark tank and removing the ladder were important parts of a successful zoo. I wish the Zoo Tycoon series kept the same level of freedom the original has, the new one was depressing to play.
The Moraff adventure games. Moraffs World and Moraffs Dungeons of the Unforgiven.
Also Castle of the Winds.
It's either tough or impossible to get purchased copies of any of them now, but that means there are sites willing to host the full unlocked versions of them now. As far as I know, the creators of both are still alive though. So I suppose if you tried really hard you might still be able to get money to them.
In both cases they were games I played when I was a kid and they stood out as games I wanted to come back to when I was less bad at stuff. And in both cases I did, and little me was right.
I remember the death messages of Castle of the Winds: RIP Killed by Huge Ogre or RIP Killed by Kobold. I had never seen or heard of an Ogre before and thought it was "org" so I pronounced it that way too for the longest time. Until Shrek was released.