As I’ve been baking bread regularly these days, this tool has been surprisingly handy. An oven mitt, pot holder or kitchen towel of course works fine for pulling oven racks out, and pushing them in, without getting burnt, but this tool is just agile enough and more convenient that I reach for it every time.
Alton Brown calls it an “oven fish” and recommends it in his excellent baking book, I’m Just Here for More Food. He carved his out of a broomstick. If you already have a Carvin’ Jack, a cheap wooden ruler would also be a good starting point. Don’t dismiss this simple gadget just because it’s frequently given away as a promotional item. It’s actually useful.