We've had below 0 temps overnight here lately, and one of our EE's has just started giving us a beautiful green egg for the last 3 days. We have been finding them outside of the nest box. Because of the cold temps DH put a very small heat lamp in the coop just to give them some extra heat, and also put golf balls in each of the 3 nest boxes so she would know where the eggs belong. He went out to feed them this morning, and found all 3 of the golf balls centered under the heat lamp in the middle of the coop! Funny chickies!