So many.

Doom, the og, first FPS... we had Wolfenstein 3D before that but it always felt like it was a demo of something to come for me. Doom felt like it stood on its own. I couldn't play it at home, had to go to a friend's house to play, for two reasons. 1. I couldn't run it, and 2. My parents were kinda uptight... they loosened up over the years, but it kept me from a lot of good stuff.

Quake was the next one up really land at least on PC.... we had a lab of Pentium computers at school that were all networked with what I now know is called 10Base5 or 10base2 (not sure which)... it was the first "real" network we experienced, and it was great. At the time those premiums were basically brand new, state of the art machines..... the teacher was cool enough to let us use the lab to play quake over the lunch hour sometimes... so we had quake LAN parties over lunch.

On PC, there were a lot of greats, but nothing too groundbreaking until half-life... but I'm guessing most people experienced that. I'll give an honorable mention to unreal and unreal tournament as well (every version). Bluntly, UT was significantly better than quake arena.

We had a short list of consoles over the years. But I have to take my hat off for final Fantasy (either 3 or 6, whatever you want to call it, the one on the SNES)... which I was obsessed with for a while there. We only had three consoles over the years that I recall... the NES, SNES, and genesis. After that, we couldn't continue to convince my parents to keep buying consoles. I eventually picked up a PlayStation, but that was a long time later.