The Ganzfeld Effect

The ganzfeld effect happens when you put your mind in a sensory deprevation experience. You can do it by putting a blanket over your eyes and listening to white noise.
After a minutes or so you will start to see blurry shapes. They will get more clear as you do it. You may also hear sounds.

Things I've seen

Things I've heards

You can have bad experiences with it though. One time I had one that was the sun exploding and destrying the earth. When I stopped a screaming green man appered suddenly and startled me.