I use it for birdfeeders...not just the fat from my own deer, but I am happy to take any extra that the meatcutter has, and he's usually happy to give it away.
I just built a new suetfeeder last week: 9 inches wide, 2 inches deep, 30 inches tall. That makes a total of 7 suet feeders around my yard, and they attract several species of woodpeckers (including Pileateds on the big feeder...Pileated Woodpeckers are the size of crows and very impressive), nuthatches, chickadees, blue jays and magpies. Fill'em up after deer season, and they're usually completely empty by the end of the winter.