[ Hermit : While Mental Floss might well be described as "The Graduate's News of the World" I thought it worth repeating. Note that the arguments above, that brain contents are irremediably lost on cellular death, precluding meaningful resuscitation of the self, will remain valid despite possible advances in low temperature cadavar storage techniques. ]
At cryonics facilities around the globe, the dead aren’t frozen anymore. The reason? Freezer burn. As with steaks and green beans, freezing a human body damages tissues, largely because cells burst as the water in them solidifies and expands. In the early days of cryonics, the theory was that future medical technology would be able to fix this damage, along with curing whatever illness killed the patient in the first place.
Realizing that straight freezing isn’t the best option, today’s scientists have made significant advances in cryonics. Using a process called vitrification, the water in the body is now replaced with an anti-freezing agent. The body is then stored at cold temperatures, but no ice forms. In 2005, researchers vitrified a rabbit kidney and successfully brought it back to complete functionality—a big step in cryonics research. (It may help in organ transplants someday, too.) But science has yet to prove that an entire body can be revived. Even worse, some vitrified bodies have developed large cracks in places where cracks don’t belong. Until those kinks get worked out, the hope of being revived in the future will remain a dream.