Hypnogogic hallucinations occur on the edge of sleep, to explain--they're the ones where you believe that you're awake, getting up, moving around, and so forth, but you're not. Sleep paralysis is keeping you from doing any of these things, but you're still trying to, and your brain, in a desperate effort to oblige, is feeding you the sensory input (often extremely vividly) of actually getting up and doing these things. They're supposedly more common when falling asleep than when waking up, but I tend to get them more on waking. Lots of the classic out of body experiences--including the ones with phrases like "but it was so real!" and "I knew I wasn't dreaming!" are actually classic hypnogogic hallucinations. Many people experience the sensation of floating while having them, and if you don't know what they are, it can be pretty woo-woo-riffic.
Hell, even knowing what they are, they're pretty neat.
I was napping on the couch, having an oddly sinister dream, in which someone (an old man? I think?) had let an evil spirit into the area. He'd been looking at some abandoned kittens and said, rather sadly, "Can't you do something for the poor things?" and the evil spirit was able to use that as an open-ended invitation to wreak havoc on everybody (who, after all, could be considered poor things), thereby demonstrating the need for specific nouns.* So this evil spirit was able to take on a vaguely human form, and was doing a lot of fairly bad things, and people couldn't walk outside at twilight, and for a brief period I was an old woman hearing it knock on the door and offer me money, and knowing that I couldn't NOT open the door, and slowly was walking very slowly to the front, because if I could keep it waiting long enough, it'd be become trapped in my area until dawn (or something like that.) There was another weird section where I was a dead girl, trying to remember what had killed me, and kept asking this other strange inhuman girl--in a women's bathroom with green marble floors--what had happened. Finally she allowed me to remember, (after someone killed her off, and I had to wait for respawn, thank you, WoW) and I spent a peculiar period watching my best friend (a young man) clean the axe he'd killed me with, and generally try to clean up the crime scene. The odd thing was that I didn't feel particularly mad at him. It was more of a "Man, that sucks. Hey, you missed some splatter over there." Perhaps it's easy to be philosophical as a ghost, or possibly I just blamed the nameless malevolent entity goin' around.
But anyway, the hallucination.
I woke up. I was very groggy. I fought to get my eyes open, they kept closing. The light through the sliding glass door was awfully bright. I thrashed about a bit, pulled the blanket off, got off the couch, walked to the glass door, looked out, saw a hole in the tree with an owl with half-lidded eyes. (There was nothing dream-like about any of this--if subjective experience was the only criteria, this actually happened.) I thought "Wait--"
I woke up. I was very groggy. I fought to get my eyes open again. The light was bright. I flapped my left arm vigorously, trying to get it to move, and sluggishly it began to respond, except that it wasn't. I saw it, I'd close my eyes, and realize immediately that if I couldn't SEE it (hand flopping quite accurately around on the wrist), I knew it was laying next to me. I cursed a bit, made a superhuman effort, pulled the blanket off, got up. I went to the glass door, looked out, saw the tree ended in a stump jogged to the side, with a dead rabbit lying limply across it. I thought "Wait--"
I woke up. I fought to get my eyes open, which was REALLY hard this time--the light was bright, and the bare branches outside were black lines across it. I opened them, closed them, opened them. I thought "Oh, no. I'm not falling for this shit three times." I thrashed around, jacknifed my body on the couch, thinking "Bugger, I bet I'm not even really moving," and with a staggering and very sideways JERK--
I woke up. I moved. Wasn't that hard. Hard to keep my eyes open, still, but not so bad. Sat up. It was getting dim out. The light wasn't really bright at all. I stood up. There was a half-full Coke on the table. I drank it. Whatever hallucinations can do, they have a hard time generating the acid-burn of Coke. I staggered to the bathroom. I discovered we were out of toilet paper. My brain, if it's making this up, is a real jerk.
However, not being one to waste time on am-I-a-woman-dreaming-I'm-a-butterfly crap, I think I've been conscious long enough to accept this as reality. Or good enough.