Saw this on Global news this morning and thought it was a good idea.
Since almost all of us carry cel phones now, and we're in a dangerous sport, you add one entry into your cel phonebook labelled "ICE" with a number of the person to call in case of emergency. This person should be somewhat close in case they have to come to a hospital or whatever and they should know your medical history. You can add multiples by using ICE1, ICE2, ICE3, etc.
Ideally you should carry an information card with all relative information, but for those that don't, take 30 seconds of your time right now and put an entry in your cel phone!