i heard of this game a while ago but i don't remember the name. I know its an older game but im not sure what system its on. What i remember about the game is that when your in the dark your character starts to go insane. The walls may start bleeding, you may talk to your dead grandfather, and the game will do wierd things like mute the volume or other things to trick you.
It's for the Nintendo Gamecube, and it employs the Sanity Effects that you describe. Other effects include a mock wipe of data, realistic bugs that appear on the screen, make you smaller as you walk down a hallway, and even blank the television. From what you say, this game sounds like a close bet.
