There is a species of frog I read about that, because of a higher sugar content in its cells, formed ice crystals with more sides that humans. Because there were more sides the points were less pronounced and the crystals for the most part did not damage the frogs cells. The frog could be completely frozen for an period and be thawed and still live.

I am not sure how long the frog could freeze for though. I'm sure if it was frozen for too long when it thawed it would not resume living.