There is Kundalini yoga http://www.kundaliniyoga.org/ and the circulation of white light , or middle pillar . I know nitrous oxide is also know as laughing gas . You will want to be care full messing with nitrous oxide . On flat liners the movie , it was a ok movie . As I remember the movie from many years ago , they used a drug , or some thing to stop the heart and simulate death . I think people from there past they had hurt came back to haunt them . Kind of like a past life review . desert rat