On a recent trip, some guys froze beer into the bottom of their coolers, in a walk-in, with just enough water to cover the cans. They only had the cooler in the the freezer for a day or so, so it did not freeze the water completely, but we were chipping cold beer out of the ice on night 6.
Another guy on the trip froze a case of rolling rock and that seemed to work, but I didn't taste any of that crap to verify the result.
I heard of this method, and am going to try it for a late Aug mfs this year.
Take all the cans out of the cardboard case/12er, then "line" the box with a garbage bag or two, replace all the cans. Put some duct tape around the box so that it'll hold up to the weight. Fill the bag with water, thus surrounding the beer inside the box, and freeze.
Now you have block ice, and tasty cold beverages...