I suffered from sleep paralysis for years.
Or, more accurately, hypnopompic hallucination - otherwise known as Night Terrors.

It would start with paralysis. Then the hum would begin. Something invisible would press me down into the matress. Then the bed would rise from the floor and begin to thrash around in mid air. It was the most terrifying experience I have ever encountered and I wouldn't wish it on my worst enemy.

A few years ago it started to happen on a night when I was particularly exhausted. I shouted angrily in my mind "Fuck off! I can't be arsed with this tonight!" and it stopped immediately and, touch wood, hasn't happened again since.
( Slippery Jim Seeking a psychotic lady for fun & sex & crime., Thu 3 Jul 2008, 15:15, Reply)