Doom 3

      Jesus. Christ. I was playing Doom with the lights off and the sound up to the max, and I'm walking down this hallway, and all the sudden all the lights go off, so I'm sitting in total darkness, and the game is playing this heartbeat noise really loud and fast, (but not as loud and fast as mine) and all the sudden there's this huge thunk outside my window., like a corpse, or a demon, or a friggin' zombie. God-damn cats almost made me shit my pants.

      Then, 5 minutes later, this little bastard is crawling on the ground towards me, and one of the cats brushes against my leg. I was so freaked that I Alt-F4'd the game, and I haven't restarted it yet.