The Neverhood, Grim Fandango, System Shock games, and Carmageddon for me.

System Shock 2
Blade Runner
Nocturne
Last Ninja games available on PC
The Bards Tale Trilogy
Hillsfar
Alone in the Dark (New remake version)
Chicago 1930

Probably a few more, just can't think of them at the min

Settlers 1
Xcom and Terror from the deep
Most Lucas Arts adventures;)

X-COM for sure;
probably Titan Quest (if it costs more than 15$ probably I'll give it a second thought).

Settlers 2 10th Anniversary Edition.
Goldbox games.
Eye of the Beholder games.
Microprose Flight sims (F15 Strike Eagle, F16 Fighting Falcon etc)

X-Com: UFO Defense
Prince of Persia (the original game)
Civilisation
System Shock
The Secret of Monkey Island

I can't really think of any instabuys nowadays, simply because I am not _that_ anxious to get to play some game I don't have already (and I already have more games than I could possibly play for the rest of my life, I think).

I'm interested to see and play many games, both old and new, just not very anxious to start playing them right away. Hence, I don't normally see the point of acquiring them right away, unless I fear I might not be able to do that in the future. Mass Effect 1-3, Dragon Age 1-2, KOTOR 1-2, Spec Ops: The Line etc. Sometime...

From GOG and such, I sometimes might instabuy without a discount to make a statement how much I approve that the publisher decided to release it (e.g. in GOG, or at least DRM-free). But these are rarer cases.

That reminds me: Space Pirates and Zombies might still be such a game, if the publisher either released it in GOG, or decided finally get rid of the DRM on their own site.

I'd give my right bollock for BOLOK

The only game I can think of that would be an instabuy for me is the first Legacy of Kain game. It's the only one I haven't played.

I'd probably be compelled to put my money where my mouth is should a new, AAA game find its way here (however unlikely that would be, save for CD Projekt's next outing).

But in terms of classics and things with a realistic chance of appearing here... yeah, I think it's basically the original Blood Omen.

It is. I took a liberty with the second 'O' in a weak attempt at humour.

FTL and Torchlight 2

Rome: Total War
Age of Empires 2
Company of Heroes

One definite buy would have to be

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