Road Safety
ICE NUMBERS
I believe the East Anglian Ambulance Service started a campaign to get people to add ICE (In Case of Emergency) numbers into their mobile phones. the idea being they know who to call first ICE. You can add as many numbers as you want by putting ICE1, ICE2 etc.
However, this may confuse some mobiles, with the result of no caller id being displayed when one of your ICE numbers calls. Though, it seems newer phones, like mine (a year old), do still display the correct caller id.