Well, my cochin went broody about two weeks ago. She stays on the eggs, now. She does get off the nest to poop and walk around a little, but the other birds bully her, so she doesn't stay off for long. I have started putting a little bowl of water and one of food in the nest box with here so she gets some nourishment. One of the things I've noticed is that the eggs can be cooled longer than I thought and still be viable. She had cracked one of the eggs and so I removed it and opened it. The 13 day embryo's heart was still beating for quite awhile before it stopped.
She has also had a couple of accidents - broke one egg in the nest and cracked a couple of them. I guess she's new at this whole thing as well!