1) Finishing Cholo on the BBC Micro - Wireframe adventure game, the game ends by crashing a plane into a base, whilst being shot at by sentry bots. Was quite a tricky game in spots.
2) Finishing Another World. Great game!
3) Finishing Flashback. Was difficult to get into, but once you got the hang of it was great fun.
4) Finishing Dungeonmaster on the Atari ST at a mates house. Seemed like we waited an eternity before Chaos Strikes Back came out.
5) ChronoTrigger, Secret of Mana, Final Fantasy IV, Shadowrun, Legend of Zelda, and some of the other JRPG's I played on the SNES. You invest a lot of time in these games grinding up levels... a wee bit sad when they're done!
6) Shenmue I + II. I'll second what someone else said earlier about this game. A must have. Shame there wont ever be a Shenmue III ;-(