Out of Body experience........

Let me first write what I mean by Out of body experience.Out of body experiences are those curious, and usually brief experiences in which a person's consciousness seems to depart from his or her body, enabling observation of the world from a point of view other than that of the physical body and by means other than those of the physical senses. Thus, an out-of-the-body experience can initially be defined as 'an experience in which a person seems to perceive the world from a location outside his physical body' . In some cases experients claim that they 'saw' and 'heard' things (objects which were really there, events and conversations which really took place) which could not have seen or heard from the actual positions of their bodies.
More curious still are reciprocal cases of OBE and apparition: the OBE subject, aware that he is operating in some kind of duplicate body, travels to a distant location where he sees a person and is aware of being seen by that person; this person confirms that he saw an apparition of the OBEer at the time that the OBEer claimed to be in his presence. Thus the two experiences corroborate each other.
But my pondering is that , is it possible to have such experiences at will? Or is it possible to exchange bodies with somebody to learn what your physical body does not allow you to learn coz of circumstances,limitations etc etc. Lets say for few months. Do you think its fantasy or weird or just impossible!!!