The first fabulous use of the freezer was as a chick brooder. We turned the freezer on it's side, so that the door opened like a hatch, and the largest surface area (the side of the freezer) was now floor space for the chicks. We laid down cardboard and some coarse sawdust, installed a light bulb on the ceiling (after snipping the electrical cord to the freezer, and re-using it to splice on a light fixture). And screwed in an eye-hook on the door, and a latch, that holds the freezer door open just a bit to allow ventilation. For the first few days the chicks needed supplementary heat. We use hot water to radiate heat. I made a slip pillow to put around a 5 gallon bucket (any bucket, or pot, with a tight fitting lid that fits inside the freezer, and will not be needed again in the house, will work). The pillow around the bucket keeps the chicks from burning their selves as they warm themselves against the bucket, the same as they would under a heat-lamp. For about a week I refreshed the bucket with not quite boiling water, just to the steaming and tiny bubble phase, twice a day. As early in the morning as I could, and as late in the evening, to keep them warm over night. We had a thermometer in there and it kept at a pretty consistent 30-32C. Watching to make sure that it doesn't get too warm when a fresh bucket is installed, in which case I would open the door a bit more, and close it again when it stabilized. After a week, the chicks started making their own heat, and as the freezer is designed as an excellent insulator, their own heat was radiated back to them, and the hot water buckets were no longer needed. At two weeks I had the door open about 6 inches during the day, with a clear plastic window to keep them from hopping out, installed like a child's barrier 3/4 of the height of the opening, again to allow ventilation. By the end of three weeks, the chicks were gradually exposed to outside temperatures, and ready to be moved out of the brooder.Encouraged by our success with the brooder, we tried it as an incubator. It was a bit harder to keep it up at 37-39C than it is to keep it at 30C, meaning boiling water changed more often. I also made the latch to close the door tight to hold heat well, and taped small sticks around what would be the top edge of the freezer, so that when the lid was closed, the rubber seal around the lid was held out enough to make ventilation gaps. And by moving the freezer-incubator to a part of the house where the temperatures fluctuates less, we were able to incubate eggs without power! The best part about using hot water as a heat source is that it is also a source of humidity. The humidity meter read at a constant 50-60%.
Now for the fridge, when we moved the young chicks outdoors, they still needed a warm place to huddle at night, so we put the fridge on it's side and took off the door. By propping the door against the fridge so that it covered 3/4 of the opening, and just left a gap for the chicks to go in and out, we had a cozy little spot for the larger chicks to keep warm at night.
Now the fridge has been measured and evaluated as a kid box. For the first two weeks of the kid's life, they cannot produce their own heat very well, and need an insulated box to keep warm. Our fridge was a small model, and is not quite adequate, but if it were a full size fridge, it would work very well as an insulated hidy-hoe for kids and lambs.
They also make convenient storage containers for potting soil or as instant raised beds for urban potato growers, etc (You will just have to work out the drainage issue). And in spring can be used as cold frames for transplants. With glass or plastic over the top, and the lid off in the daytime, they will keep plants insulated, holding the heat from the sun like a greenhouse. Just put the lid on at night to keep the frost out. Of course you can also add coffee cans or plastic bottles of hot water at night and on cloudy days to keep them growing.
Or the fridge/freezer can be turned into a big sophisticated version of my camp cooler, with a small pump running cold well water into the basin, and an overflow pipe running water away, to keep your perishables fresh.
Any other ideas?
So next time you see a defunct fridge or freezer in the ditch on big-garbage day, and you have already used up all of your own fridges and freezers for various brooders and cold-frames, you can rescue even more from landfill. And you get a free extension cord thrown into the bargain.