....to skid on in wet weather:
http://news.bbc.co.uk/1/hi/england/south_yorkshire/4928000.stm
http://www.drivestop.com
I'm more than half inclined to suspect that the spikes bit is a hoax,
given the extreme reticience of the site to show the system in action.
But even so, the metal plates look seriously unpleasant in wet weather.
R.