Everybody's missing the point. I believe we're talking about virtual display device, just as there is a virtual CD drive (like the one with Alcohol120% or DaemonTools).
The idea also came to my mind when I tried to play the game Pathologic but the picture wasn't good on widescreen, it doesn't have windowed mode, it can't be tweaked and I'm sick of having played Diablo2 stretched from 800x600.
A virtual display window should be something like a 800x600 window on my 1280x800 desktop (think of windowed Quake 3). I searched the web but AFAIK there is no such thing (yet).
There is a utility to emulate hardware TnL (required for most games nowadays)(see http://www.3dfxzone....3d_analyze/download/
), but that's not it either.
There is an old utility someone made called DXWnd that supposedly runs non-windowed games in a window. Won't work for me (either XP or Vista machine), plus it's directx version-specific.
I'm not sure if this is even possible,
if it is, it would need a virtual device driver (any volunteers?).