I am currently reading my way through a long list of science fiction and fantasy titles. (http://www.npr.org/2011/08/07/138938145/science-fiction-and-fantasy-finalists if you are interested in the list).
Do space agencies ever discuss human hibernation? They have and they do. "It never dies," says John Charles. "It just hibernates.
Mary Roach, your sense of humour & curiosity match mine so well--we would either be BFFs or annoy each other to death!