I've been having a kinder, gentler version of night terrors; I see things, but they're (usually) not frightening. Often there's a missing wall or a hole in the ceiling; I've seen clouds and fireworks and the occasional bird or squirrel or something on the curtains. Once I saw hordes of butterflies covering the walls; another time there were about 50 sofa cushions stacked in the corner of the room. Last night it was blue helium balloons, like a birthday bouquet. I sit up and put on my glasses to try to see more clearly whatever IT is; usually it takes 30 seconds to a minute for the figure(s) to fade away.
I'm sure this phenomena is related to stress; my girlfriend's father was dying of cancer all fall and winter, and died two weeks ago. I was pretty proud of the fact that the "night sights" had stopped for a few weeks, but then they came back. I do sleep on my back, so that might be related somehow; all I know from the reading I've done is that it happens during non-REM sleep, and is often related to stress. I get them frequently when traveling; it makes sense that it would happen when I'm in unfamiliar surroundings.
The more I think about it, the more amazed I am at how powerful our brains are, and how we are completely at the mercy of what our brains tell us is reality. Take schizophrenia, for instance—especially the visual hallucinations as presented in the movie A Beautiful Mind. For that first half minute or so, my “night sights” are completely real to me; I can only imagine how difficult my life would be if they didn’t fade away, and in fact stayed around, or (God forbid) spoke to me and interacted with me on a regular basis.
In A Beautiful Mind John Nash eventually realizes his doctors are right, and his hallucinations are just that—manifestations that are not real to anyone else—when he notices that one little girl that he sees never ages. I feel fortunate that my “night sights” have not been as terrifying as what Protector of Mankind and DoctorNo describe above; I have the odd experience of slowly realizing that they cannot exist. On one occasion, for instance, I knew the man standing over my bed couldn’t be real, because I could see furniture in the bedroom, and the man was not to scale with everything else.