pac - You must get these things on the Lake Erie shoreline. We don't get them here on Lake Simcoe but they get a lot of them up on Georgian Bay.
Holy cow! Are you guys shooting those at us?!
I have never seen them. We get lots of ice dunes though, which are pretty neat looking. They are like rolling hills, or dunes, formed by the waters along the shore, but they are hollow inside. Every once in a while someone will fall through one into the lake. They can get quite high above the surface, 10-15 ft.