Idk how well this would actually sell but years ago in my early 20s, I came up with the idea for a beer coozie for 40oz bottles.
40s are great if you are poor and want just enough of a buzz but unless you chug them, they get warm halfway through. Which is also why 12oz cans/bottles are probably also more appealing.
Just a big ass coozie to keep your Bud Ice cold in a Sunday afternoon of porch drinking.