I played Amnesia: The Dark Descent alone, on a couch in my old studio apartment in lower Manhattan. Some fish live there now, but nevermind. Anyhow, the apartment was basically a room with no insulation from the city, so I felt like I lived in the middle of Second Avenue. It was not a particularly private place.
The night I played the game - and I played through it in one sitting - was the most solitary experience I ever had in that room. I had headphones on and my laptop on a pillow on my lap and I forgot about the outside world. I was deeply frightened, of course, but what I remember more was the way I was just totally not cognizant of anything other than the game's sights and sounds. It was one of the most memorable gaming experiences of my life.
In honor of Helloween (see what I did?), Frictional Games released today a trailer for the followup, Amnesia: A Machine for Pigs. It looks like the Dark Descent but with a nastier edge. That, dear readers, is a scary thought.