A variety of nondestructive techniques have been proposed:
Unfortunately, both gamma rays and X-rays would have about 100 times the energy needed to vaporize whatever they hit, so this is not likely to be as nondestructive as it sounds.
[Editor's note: these techniques (except for the last one) were taken from an article called "Uploading", by Yvan Bozzonetti, cryonics mailing list message # 3241, reprinted from Cryomsg #3212. Some of the refutations come from Robert Reid at the University of Toronto. Correlation mapping was proposed by Keith Lynch in Cryomsg #3326. Many thanks to these contributors.]