I was looking for info on Hangl plates and stumbled across it. Click on the picture and let the next page load, then click on "product". The have all of the available Hangl plates on there. They make some crazy looking stuff that I would love to throw on a pair of 150 hypercarvers. I think it might be possible to carve a circle in the snow with some of those contraptions
The page is in German but I think if you locate it through Google it will translate it for you.