Can anyone recommend something like ice grippers which you put on the soles of your shoes in icy weather to stop you slipping and falling over on the ice?
I think LL Bean has grippers that slide over your shoes. You can buy thenon line at LLbean.com or check out google.com or amazon.com
Yak Trax go over your shoes or boots, and provide excellent grip. They're available at sporting goods stores.
You can buy them from the Vermont Country store on line catalogue or buy some stainless steel "scrubbers" and stretch them over your shoes.
This is not really answering your original question but just some info whether you have extra traction for your shoes or not. If you walk flat footed instead of heel to toe (and slowly if need be) your chances of slipping are very greatly reduced. I learned that living in Michigan for 16 Winters where there was always at least one ice storm a year and lots of ice build up no matter what. ;-)
Most sports sections of stores sell rubber with prong deals that fit your shoes or boots. In a pinch my father in law would slip rubber jar rings from preserving jars over the front of his footwear. This was on the farm, not too cool for town, I guess.