Weightlessness, Out of Body Experience.

I have felt so many times during sleep that i am going weightless, i am going through a long tunnel or pipe.
My hands could not move, my legs could not move , i could not even speak anything. It feels like if some power is pulling me out of my body. That is the time when i am not in a sleep, i know that i am awake but i can not move my body parts not even the fingers. Earlier i used to get scared by these things but now i enjoy this out of body experience. Earlier it was not in my control, that is, this used to happen on its own, but now i can do it on my own wish. I feel as if i am floating above my body.