I wrote this as a comment at another blog. Seems appropriate to post the brief bit here:
When I was in college just after high school, there was a retired Air Force pilot in one of my classes. He recounted how, during a heart operation, he KNEW that he was floating above the operating table looking down on his own body and the physicians and nurses.
A classmate said, "Man! You had an out of body experience!"
And the pilot said, "No, I had a goddamned hallucination, you dumbass.
I don't recall that pilot's name, but he remains foremost in my mind as a right thinker.