I can't be the only one. What games do you always have installed on your computer (or console, even, these days)? The ones you know that -- no matter what else comes along -- you're always going to go back to them.

For me, aside from the small older games like virtually all the old adventure games from Sierra and LucasArts, I always have the following on my hard drive:

Escape Velocity Nova
Neverwinter Nights
A Civilization game (currently Civ 5)
Sid Meier's Pirates
Tetris

Also, Fallout New Vegas has been on my computer since I got the game, but it hasn't really been around long enough for me to know if it will join the list...

I can see that (for Elder Scrolls, I've unfortunately never had the chance to play System Shock). For me, they tend to go in cycles. I play them for a while, then lose interest for a while and they get removed when something else needs the space. Right now, I suppose New Vegas is taking the place of ES games. Maybe once I start getting into Skyrim mods that will change...

Doom always makes it on all of my computers when I use them, in many different forms I might add.

GTA Vice City is pretty much always installed.

Duke 3D has been installed since I bought it here.

Audiosurf is on my systems as well.

Zeboyd games: Breath of Death VII and Cthulhu Saves the World.

Just some stuff that's always fun to mess around in for either brief stints of time, or extended periods, depending on what you feel like.

Pro Evolution Soccer (which ever version I play at the moment)

I can't say always, because now and then if I haven't played something for a long time and don't expect to, I uninstall.

But the games I always go back to are Warlords 3 Battlecry, VTMB, Mount & Blade Warband, the Spellforce series, and... that's about it, I think.

Well, I guess I could throw Guild Wars into that category too, though I feel much more strongly about the other games.

My list is fairly small:
Master of Orion 2
Heroes of Might & Magic 3
The Settlers 2
Descent 1+2
Unreal Tournament '99

But there's a good few probable future additions (which have been on two computers or less thus far):
RollerCoaster Tycoon 3
Locomotion
Startopia
Master of Magic
King of Dragon Pass
Alpha Centauri
Stronghold + Crusader
Wing Commander: Privateer

X-COM: Enemy Unknown (UFO Defense)
Fallout 2
Planescape: Torment
Baldur's Gate 1 & 2
Counter Strike
Left 4 Dead 2
Uplink
Jagged Alliance 2

I try to keep a variety always installed since I have limited hard drive space (which will hopefully be changing soon and I can just install everything I own and never have to wait for downloads again *insert evil laugh*). And of course most of these are classic titles that I can always play and try something different.

A good question. Not counting the thousands of installed DOS games in DOSBOX, here's my list:

- GTA Vice City. Driving around the city listening to 80's music remains very entrancing.
- at least one of Bethesda's games. Mostly Fallout 3 since I just love the combat.
- Beneath A Steel Sky (DOS game but even then, it has never left my hard drive)
- Guild Wars 1&2
- Diablo II (although I rarely play it)
- a whole range of indie games

It was installed without your permission! Sue them!

Other than that - Minecraft is a permanent fixture on my PC.

Hmm, I usually have the following games available to me on any given PC:

Ultima 7
Deponia
The Dig
Monkey Island 1 and 2
Guild Wars 2
Warhammer 40k: Dawn of War II - Retribution (don't own much of the DLC though)
Torchlight I/II
Infinite Gameworks: Episode Zero
Neverwinter Nights
(At least one) Tex Murphy game
Binding of Isaac
Super Meat Boy
Grim Fandango
Day of the Tentacle
Full Throttle
Psychonauts
Wing Commander: Privateer

I kind of want to get the System Shock games (AT LEAST SS2), as my ex-roommate made off with my old copies :(. I rather not "Sail the 7 seas" for them; I guess I'll have to go with either eBay or Amazon.

Fuel and all the FATE games. Warlock - Master of the Arcane may be another that I'll keep installed too.

Apart from those, there's a few others; but the only reason those remain installed is because they required rather annoying workarounds to get them installed and running (such as Sacred 2 Gold).

Besides some games that were already mentioned, I keep and still frequently play Dungeon Crawl Stone Soup, Battle for Wesnoth, and Mount and Blade Warband.

Master of Magic. Still unsurpassed.
Jagged Alliance 2. I do need to do some testing to see if new features work, best to keep it installed all the time.
UFO: Aftershock. One of these days, I will finish it, have been trying to do that since 2005.