The first time it happened I thought I was dead, because I felt completely conscious but could not control my body nor receive input from my senses. I kind of panicked, and with what felt like an extreme effort was able to become fully awake.
Since then it happens from time to time (I can't make it happen) and it's a very pleasant experience since you're in a dreamy state where you can pretty much decide what you dream about.
It's a state that is between awake and asleep; when in that state, it's very easy to fall into actual sleep (to lose consciousness), and very difficult (but possible) to awaken completely.
I keep good memory of the experience each time.
I would like to talk about it with people who experienced the same thing, but could never find anyone just by talking about it to friends around me. Where should I look? Does this thing have a name?