It’s sort of a nice thought, getting frozen indefinitely. You can bide your time inside a chamber cooled to a balmy 321 degrees below zero, until humans find a way to turn you into a zombie — at which point you can emerge with your outdated haircut and weird clothes. Sounds appealing, right? You’re basically a time traveler.

What We Can Do

A quick disclaimer: Getting cryogenically frozen doesn’t mean your rag doll corpse is just dropped into a vat of liquid nitrogen. Cells are mostly water, and water expands when it freezes. (If you’ve ever taken chicken out of the freezer to thaw, you know what I’m talking about.) Basically, your cells would shatter and die.

Getting frozen forever (or until science can reanimate your freezer burnt self) — a process formally known as “cryonics” — requires substances called cryoprotectants. Think of them like the antifreeze you put in your car. So far, our greatest leap forward in preserving our own species and bringing it back to life is on the tissue level, and small ones at that. These include ovaries, embryos, plant seeds, blood, and semen. Larger tissues, such as hearts and livers, let alone entire bodies, require loads more cryoprotectants and, thus, are harder to preserve.

Still, the effects can be mind-boggling. In May 2006, the second of two twin girls was born 16 years after her sister. After a long, storied battled with pregnancy complications, including three ectopic pregnancies and 10 miscarriages, the girls’ parents decided to delay fertilizing the second of the twin embryos. When the initial sibling embryo fertilized, and eventually grew up into a healthy teenager, the family decided in 2005 to revisit the idea.

"We feel incredibly lucky that we've finally been able to complete our family. It's been a long and traumatic journey, but we're so glad we never gave up," said the girls’ mother, Jane Davis, according to BioNews.

What We Want To Do

So we’re making waves with embryos. But what about you? You’re already a person — who will not only die, but, if things remain the same, stay dead. So what’s a person seeking immortality to do?

Enter Robert Ettinger. Aside from being the 106th person to be cryogenically frozen at the Cryonics Institute in Clinton Township, Mich., he also happens to be the Institute’s founder. Ettinger first learned about cryonics in a science-fiction novel he read as a kid, and it was a fantasy he refused to abandon as an adult. Inside the building, over 100 people float limply inside large white drums, including Ettinger’s mother, his wife, and his second wife. And when nature takes its course on Ettinger’s son, David, he too will take the hopeful plunge.

"He believed like a lot of people do that in the future we're going to have dramatically better medical technology,” Ettinger told ABC News of his father. “The question is how do you get them from here to there, and cryonics is kind of an ambulance to the future.”

That ambulance is decidedly complex. Fork over $200,000 for a full-body preservation, or $30,000 for just your head, Ted Williams-style, and you’re entitled to a full vitrification process. Scientists sap your body of its natural water supply and replace it with a sort of “solid liquid” that keeps your cells in suspended animation and ice crystal-free.

Critics uninterested in living forever, or at least in spending 200-grand to do so, happily point to the zero frozen patients that science has managed to revive. Keeping a person at the appropriate temperature is expensive, and many people quit funding the endeavor before any scientific advance quits it for them. This leads many people to question the true intention of companies like Cryonics Institute. But then again, if you have $200K to blow, why not live forever?

All this points to a curious dilemma. On the one hand, we’re edging closer and closer to preserving the sum of our parts indefinitely. (Recently, scientists used 22-year-old frozen sperm to fertilize an egg.) On the other, people who are in the position to take a chance at immortality seem to be taking advantage of it — even if the freezers are turned off before the decade’s out.

But maybe asking whether cryogenic freezing is possible misses the whole point: Yes, it’s possible; David Ettinger has a marching band frozen in his warehouse. Maybe the better question is: When can we be unfrozen? And to that I say, there’s only one way to find out.