I always wanted a pair of roller skates but as far as I remember I never got any, as a result I am not very well practised at walking around with reduced friction between my feet and the pavement. I have already broken one ankle when I slipped on the ice on the way to work  and don't intend to break the other so I am contemplating the purchase of what Norwegians call brodder and what I call Granny crampons.  There are two main types the ones with spikes in them, which seems like an obvious way to stop the feet slipping, and the ones that are springs as in the picture. The thing that interests me is how anyone found out that wrapping springs round your shoes stopped you falling over on the ice, what will they think of next.