I am reading journeys out of the body now by Robert A. Monroe interesting indeed. I heard Terence Mckenna say he got a Buddhist monk to smoke DMT, he said 'this takes you to the place, where if you went any further, you would not be able to return' and you hear people speak of this 'waiting room' all the time. Even Monroe in his book speaks of a waiting room place that you can travel to as an astral projection.