There is already much proof that people have seen things that they couldn't possibly have seen and described them and exactly where they are.<quoted text>
Actually there is a doctor who places prints of symbols facing up near the ceiling of his operating room so that the only way to see them is from above.
If a patient is able to describe the symbols after a near death experience, that would be evidence of soe non-physical aspect leaving the body.
So far, nothing.
It can't prove NDE's AREN'T real, but it could prove that they are.
*** http://www.victorzammit.com/evidence/nde.htm *** has a few interesting stories, but there are millions of examples, as you probably know :)