Currently saving a jar of it in the freezer, sure that one of you will have a genius solution for this!
Can't eat all the fat off the bone broth, nor can my dogs. Other uses?
Candles or soap. I've read that it can be stored at a low room temperature if it's processed correctly. The way it's generally done is fill a mason jar to the brim with rendered tallow (make sure the rim is free of fat or you won't get a good seal), put a lid on it (a lid that's been in simmering water, like canning), and let it cool. That will make a seal keeping much oxygen from getting to your fat.
ETA: I forgot a link.