I discovered this by chance yesterday. I had picked some blackberries, and frozen them on a tray, and when I went to tip them into a bag - lo! I found that I had mistakenly frozen a spider.
What if I am the first person to discover that a spider can survive such a low temperature? I thought. So I laid him/her tenderly on the table in the kitchen to see. S/he seemed rather crisp, but no matter. All the legs were there. Everything in tact. I waited.
An hour later, I returned. The spider wasn't quite so crisp, but it was almost certainly dead.
Telling my son about this, he reminded me of all the times when we had resuscitated hibernating hamsters by the fire, and he speculated that the flower bed which doubled as burial ground for animal corpses was probably full of misdiagnosed hamsters which had been, not dead, but merely waiting for the spring. Isn't that an awful thought?