You can make stock in it. I just pick the meat of a carcass, slip it in the slow-cooker, cover with water, and let it do its magic for 8-24 hours. I like to start it after dinner and then let it work while I sleep. Waking up and already having the stock made for dinner’s soup a) makes me a feel productive before I’ve even gotten out of bed, and b) gives me a chance to refrigerate it so that the fat hardens and can be skimmed off easily. In the slow-cooker, stock doesn’t concentrate down (unless, of course you turn it on high and take the lid off near the end), so don’t use too much water. If I wanted extra flavor, I would probably put in a quartered onion with the carcass, or celery ribs, or at least some salt and pepper. I’m not sure why I didn’t think of this sooner, but I’m glad that I realized that I could use my slow-cooker this way.
Another reason to love your slow-cooker