Have any of you ever gone to sleep, and had your mind wake up before your body? I've read about it, and it's not a rare sleeping disorder, per se, but it's also not common. Basically, what happens (from the "end-user" perspective) is this: you wake up like normal, and try to move, and can't. Breathing is difficult, movement is impossible, maybe if you struggle you can pry your eyes open... but that's it. I know for me it puts me in a state of panic. You feel utterly paralyzed and helpless. For some reason you gain consciousness while your body is still asleep. The breathing difficulty is simply because your body is still in "sleep mode" while your brain is in "panic mode", and "panic mode" expects a lot of fast, shallow breathing, and sleep mode tends towards slow, deep breathing. So there's not actually any trouble breathing, it just feels like there is. And that, of course, adds to the panic.
It's apparently related to narcolepsy (don't you love that word? I know I do...). Actually I suffer in some small way, or have at times, from almost all of the symptoms listed here: http://www.sleepfoundation.org/publications/livingnarcolepsy.html but I don't think I have it, as I don't suffer from any of them regularly, and the "sleep paralysis" is something I haven't had in a while. I wonder if I suffered from narcolepsy as a child, though. I found a page on sleep paralysis. So apparently it happens independent of narcolepsy. Anyway, I'm not worried, it's been over a year now** since my last 'attack', and the older I've gotten the less frequent they've gotten.
When you finally wake up, it's like... almost like surfacing after being underwater too long, where you were losing your breath and weren't sure you could make it, and at the last second when you're sure your lungs are going to burst and you're going to die, you burst through the water... that's the sort of feeling you get when you finally sit up after suffering from that. The problem is, even though your brain is racing at high speed, your body is still just barely awake, so it's slow, relaxed, calm... it's a very unnerving feeling, very disturbing. You want to get up and pace around the room and hold yourself and shake, but you can't because your damn body is mostly asleep. Sitting up and blinking is about as much as it can do, maybe stand up.
Anyways... that's my rambling for now, I gotta get back to work.
* - Yes, technically, I should be working. But... um... shhhh.
** - Maybe longer than that implies; I can't remember exactly when it was, but definitely not recently.