(May contain spoilers for MGS1 and 2. Very slight though)

Greetings,

Just looking for a game that messes with you, in the vein of Metal Gear Solid 2 when the colonel goes nuts and says to "turn the game off" and the like, MGS1 with psycho mantis, or Eternal darkness at late night. Or on another note, maybe movies like “the ring”. Something that threatens the viewer personally in some shape or form.

Basically it has to be good enough so that the player is partially engrossed in the game, to get slightly irked/freaked out when the game starts acting funky. A friend and me were thinking about a pretty evil plan to use with such a game, using MGS2 here as an example:

There are actors in the game (the pranksters), and one target (guy to be freaked out). The target and actor 1 (A1) are playing MGS2. When the colonel starts acting funky, A1 states that when he played MGS2 this never happened. When the colonel says to turn the game off, the real fun starts. Other actors will call the phones and scream, IM, or change the text in their favorite forum to "turn the game off now". One will ring the doorbell and leave a note saying to turn the game off either by the door or somehow slipping it inside. Another will be with A1 and the target, and will suddenly disappear shortly before the colonel starts his spiel. There are also target specific pranks we had in mind, but you get the idea.

Now, it doesn't seem that scary at first, but this must be done at 1:00-3:00 AM, so the person is a tad bit sleep deprived. Everyone gets a tad bit edgy with less sleep, and taking advantage of that can work wonders. Also the game must be good and engrossing, allowing a partial suspension of disbelief.

I think you found the perfect example right there...

Talk about edgy when slep deprived, in the bathroom around 3am last night, all i could concentrate on where noises outside, for some reason i thought there was something big, black and scaly outside...

Yeah, that's a great idea. Don't ask me how you'd do it. mind you!

I can only think of a couple of games, but they're not really quite the same as your example, They'll just mess you up in a scary kind of way:

AvP2 (Aliens versus Predator 2) - try playing that game alone, at night, with all the lights turned off, with a subwoofer and good speaker, and . . .

Yeah, I just remember the first level you are as a marine and you don't shoot anything for AGES (the suspense builds like crazy). You get separated from your group, and all these weird things start happening - you're in this compound and you hear people screaming, and catch rare glimpe of bodies being dragged off into the darkness. Then your motion tracker goes wild, and starts picking up all kinds of "movement" around you, when nothing's there, and it starts to beep louder, and LOUDER - yeah the stuff messes with you mind.

Finally, you get to this place where you've got to activate the automated security system grid, and then all hell breaks lose - music starts thumping so loud you have to turn down the speakers, and you hear alien screams as they burst through vents, the ceilings, the doors EVERYWHERE!!!! AHHHHHHHHHH!!!!!

So yeah, I got kinda freaked in case you didn't notice!