Although the snow has gone, my car has been icy in the early mornings this week, this is the cheapest I have found.
I did find another deal already posted (http://www.hotukdeals.com/deals/600ml-car-plan-de-icer-only-74p-sai/842712), which is 74p @ Sainsburys, but my sainsburys doesnt have any at that price. :-(
So yeah, 600ml carplan de icer £1. btw link is to product on site.