Salam alikom brothers,
I've just had a similar experience yesterday morning...
around 2 months ago, i was not considered a really... good muslim, but i've decided to change completely.
Since November of 2010 I have never missed a single prayer, i started reading quran and also decided to memorize it, I have just finished memorizing the first joz', which means i'm reciting the first 141 verses of Bakara daily to make it stick in my mind.
So, what happened? Yesterday I slept normally, and woke up at 6:20 AM, I missed the Fajr prayer in mosque by 20 minutes, so I wake up, go to the bathroom and do Wudu' to pray Fajr in my room. I step out of the bathroom and pray normally, then I went back to bed to continue sleeping...
Sometimes I see some words like in a paper going through my mind when I try to sleep with my eyes closed, like sometimes I could read exactly like i'm reading from a book, with a very clear text, like an answer to a math problem or whatever, but yesterday what i saw was a sentence, and in the middle of the sentence was the word "ALLAH" in arabic, I couldnt remember the rest of the sentence, maybe it was "Rasool Allah" * The prophet of Allah* anyways, I loved the way it was written and i started to focus so much on the font because i wanted to try and write it in that way when I wake up later, then it all happened, i started focusing so hard on the word, suddenly the word "EBLEEES" has started echoing very loudly in my mind and so frequently, EBLEEES, EBLEES, EBLEES, and it was getting louder and louder! I wanted to say "A'ooth bellah min al shaytaan al rajeem", but I could not open my mouth at all, I tried so hard to say it, I finally was able to open my mouth and say it, although when I couldnt open my mouth, i started saying it in my mind.. then it was all gone.. I was sleeping on my right side at that moment and had the blanket over my head because the sun has started to rise and I did not want it to bother me.
I have couple of theories on this, and they both maybe interfer with each other.
The first is that, the devils has gone very mad from me, because i started praying, fasting modays and thursdays, and memorizing the holy book of allah. and as a way for them to make me stop doing this, "After everything else has failed them" is to try and scare the hell out of me!!, at first this is what i though, but I did not think of the Jathoom, rather I thought that multiple Jinn has teamed up to try and scare/hurt me...
I woke up, I started laughing and I swore to them, I said, Walla, if all of you Jinn have gathered and teamed up to hurt me, and Allah did not want you to hurt me, you all will never be able to do a single thing to me!!, and if I am to stop doing what i'm doing now *being a better muslim*, I'd rather be hurt by you than ending up in hell like all of you!!, and it really felt good... *Lets just hope it wont come again

*
My second theory was that, this happened after I have done an effort to focus on the text that has appeared to me, such text appeared to me before, but I did not really focus so much on its text.. So maybe because I focused so much, I have entered a state which I could be controlled or communicate with the Jinn...
The thing is, I became a really good muslim, i never missed a prayer, I fast extra days, and tried to memorize the quraan, and I just finished from praying the Fajr prayer and i was on Wudu', but even so, i felt sleep paralysis when I went back to Bed, so this is what confuses me. and I dont think it was a physical issue, and i'm healthy al hamdu lellah, and nothing in my habits have changed in a while. Because of this, I think the first theory was a good conclusion, as it might not be the jathoom, but rather pissed off group of demons that had enough with me not listening to what they want...
From what I read in non-islamic websites about sleep paralysis, is that the body goes into 2 phases when trying to sleep, REM and NREM, REM is the Rapid Eye Movement, and the N for "non-", and when switching from one to other or something like that, the body can go into the paralysis effect that last for few moments, so I think when I have focused so much on the text that have appeared to me, I probably have switched from one state to another, and maybe in order for the Jinn to take control, they themselves manually change this state in your body and might be their gate to you...
So what i thought maybe even though I was on Wudu, i was the one who triggered this gate for the Jinn to take control... But this whole experience lasted for about 2 seconds maximum, I think because I was a strong muslim.
What makes me think that the non-islamic scientific explanation fails, is that when the paralysis happened, words such as "Ebleees", Satan, has started echoing in my mind out of no where, and I had no anxiety, or fear of devils at all before this moment *Not that i have any afterwords also*, but maybe the scientific explanation shares the islamic-jinn explanation and they overlap with each other...
Now why did I bother with all this theory/research?? Because I am an engineer

lol, I have to do so ._.;
And all of what I wrote and Allah A'alam! Allah knows best.
Slaam