Games that i'll never forget:
SFC and it's companions, obviously. A space navy simulator that doesn't require a joystick and all that implies is a plus.
RPGs such as Septerra Core, Gothic, Morrowind and when i'm really feeling odd, Final Fantasy. Of them all Gothic and Morrowind paint the best environments, Core gives the best yarn and Final Fantasy... uh... nostalgia I guess. Played arcanum as well, but the infinity engine that's for baldur's gate/icewind dale/fallout and the generation of it that made arcanum breathe are generally too clunky for my tastes.
Emulator based RPGs such as Sieken Densetsu 3, and Secret of Mana for reason both being that they're games of fond childhood memory and contain good lessons concerning gameplay.
The old console RPG-strategy games, such as Jutei Senki, Front Mission, Tactics Ogre, Shining Force 1 and 2, Fire Emblem, and many others. Old favorites that are played over, and over, and over, and, well, you get the idea.
Shin Megami Tensei is a favorite for story and atmosphere; A very intresting mixture of modern/nuclear holocaust fiction, religion and magic. Not for everyone though, as its religious view is not particularly eurocentric.
Strategy games, such as Simcity 3K, 1602 AD, and my latest aquisition, Port Royale. The best strategy game ever made is still, however, Master Of Magic.
Dungeon Siege is a great timewaster, and has effectively replaced the solitare slot in my head. Mindless, but very nice visuals. An editor on par with Morrowind, (something I see as a benchmark for all future games) makes it very intresting to tinker with.
And last of all, Archon Ultra, the absolute last say in tactical 'thinking' games. Flawlessly balanced, yet still requiring some thumb skills to make it to a win.