Hi, mine has two cracks in it and when I get around to getting it fixed (MOT isn't due until Jan 2013) I will ring my car insurance company and tell them that my windscreen has just cracked, they will either contact Auto-glass Windscreens or a similar company who will come out to my workplace / home etc to replace it, or inform me where I am authorized to go to get it replaced. According to my Car Insurance documentation as long as I use their approved Glass Replacement Company all I have to pay is £75.00 glass excess, this used to be £50.00 but due to current financial issues it must have crept up since last time I checked or needed a new section of glass.
Hope this helps: Geoff
Hope this helps: Geoff