If you're going for slightly older games (and me having absolutely no idea what you've already got) my suggestions are:
- Independence War 2 - Newtonian Physics, 3D Space Combat
- Deus Ex - 1st person RPG
- Homeworld - 3D RTS
- Homeworld Cataclysm - 3D RTS
- Age of Empires II - Sprite-based RTS
- Descent 3 - 3D indoor/outdoor action
- System Shock 2 - 1st person RPG, like DX but entirely different...; not played
- X-Wing Alliance - Star wars Flight sim
I-War2 is bloody easy to mod if you've got the patch. It actually has a dedicated screen off the main menu to control the active/inactive mods, and there are quite a few on the community web site. However, the game's a little tricky to get the knack of. I can't remember how many times I got fragged in my first skirmish with some Marauders...
Deus Ex...I think we've all got a pretty good idea of what became of it: a legendary game. Getting the SDK lets you make your own levels/missions, and there are plenty of user-made mods out there.
Homeworld and Cataclysm are easy to mod in terms of ship stat editing. There's a special texture index that keeps the texies all nice and purty for changing LODs, but makes modding damn near impossible if you want to change just a few ships about. Although the mods out there are impressive. If they'd just make new campaigns to go along with them...
Age of Empires II is easy to play, but a ***** to master. Building walls around your base doesn't work as it used to, and even then they put up Trebuchets and hit your base right across your walls! But fun nonetheless.
D3 I suppose we're also fairly familiar with.
XWA I'm also not going into too much detail. Can be modded, but it's harder than it first appears.
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New(ish) games:
- Star Trek Bridge Commander - 3D space combat with friggin' huge starships
- Jedi Knight II - FPS with a lightsaber
- Aliens vs. Predator 2 - FPS with a massive fear factor, not played
- Star Wars Galactic Battlegrounds - AoE2 in Star Wars (or the other way around), not played
- Ghost Recon - Tactical FPS(?), not played
- Operation Flashpoint - Not played
- The Elder Scrolls III - not played
- Neverwinter Nights - also not played
Bridge Commander is, next to Elite Force, probably the best recent Trek game to be made. My only quibble is that there's no joystick support, and I've not yet gotten around to finishing the main campaign.
JK2 is based on the QuakeIII engine, so naturally it looks gorgeous on a top-notch machine. Although multiplayer mode always is a stutterfest on my comp even with graphics and audio quality at the bare minimums (and I've got a
Geforce4 Ti4400!!!. But it's still fun to play.
Those that I have not played I'm not going to say anything about, simply because I know nothing about them.