Keep an old coffee can and drain your beef or bacon grease into the can. When you have enough, melt it down. Add a little flour, some sunflower seeds and even a little peanut butter, and then refrigerate. When it goes solid, you can put in a suet cage or nail to a tree for the birds. ;)
I ask for meat cutting scraps from our local butcher. What's good to cook up for the dogs I keep and the remaining scraps are scattered along the side of a snow packed road.