I work up in the Boundary Waters in the winter doing dogsledding and we camp pretty much exclusivelly on ice as an LNT practice. Everyone I work with in the winter uses ice screws to stake out their mids, which is not the cheapest OR lightest option. When I saw people were using roofing nails I was curious how viable an option this would be. My main concern was how easily they would drive into the ice, how people were removing them in the morning (even the ice screws will freeze into the ice), and how durable, or more so,reusable they would be?
I guess worst case they sound pretty cheap, so I can always try it out when i get up there and the ice starts freezing.