There's a short story by Harlan Ellison that I've been wanting to read for some time, but wasn't able to find in bookstores during my brief visits to the States. It's about five people in a living hell; a computer system "woke up" to consciousness, but recognized it was the proverbial ghost in the machine. It hated humanity for creating it, and so killed everyone except five people who it kept in an underground tunnel system, keeping them alive indefinitely, torturing them, and mutilating them. The computer is named "AM" which stands for a few things in the story, but is meant to recall both God's telling Moses that his name is "I am", and Descartes' cogito "I think therefore I am." So the computer is an imitation God, but instead of being a God of love and goodness it's a god of hatred and evil. This kind of reminds me of Philip K. Dick's short story "Faith of Our Fathers", which has something along the same lines, except in Dick's story, it's actually God: the ground of existence is a predator, creating everything so it can consume it.
Anyway, I just found a copy of Ellison's story online, so you can read it if you think your stomach is strong enough. The title? "I Have No Mouth, and I Must Scream".