Ah, you young pups. Try this list:
1) Elite (Commodore 64) The mother of all space trader/fighter games, with the most intuitive 3D radar display ever made. Great fun! Even played "The Blue Danube" when the docking computer was on, in an homage to Stanley K.
2) Ultima 3/4/5 (Apple 2, Commodore 64, and Amiga) I'm grouping these together because I consider them extensions of the same game. Truely immersive tile-based RPG, with an innovative storyline that went beyond the usual hack & slash plots.
3) Falcon 2.0 (Amiga) An amazingly detailed and true to life flight combat simulator
4) Lemmings (Amiga) The most maddeningly challlenging puzzle game ever made, and funnier than hell too. Oh no!
5) Harpoon (Amiga) Hands down the most realistic wargame ever produced - this game taught me tons about air and sea warfare. I wish this one would get updated and re-released
6) Steel Beasts (PC) A tank combat simulator that rivals the SIMNET in Ft Knox
7) Sim City (Amiga) Build an manage your own city. Whenever I drive through downtown Detroit, I start seeing it in terms of SimCity zoning
8) Test Drive: LeMans (PS2) I own a LOT of racing games, because I use the games as training for my own race car. TD: LM has the most realistic feel to it of any racing game I've ever played; it and GT4 are the only games where I can "push" like I do in a real race car and see results.
9) Railroad Tycoon 2 (Linux) Play with trains, lose track of time.
10) Enemy Territory: The best of the first-person Quake-alikes. 100% online play, and mission-based. This is what America's Army should aspire to be.
There are more, but that's a good start.
DG