I have my Treo set to display the owners page as soon as you hit a button.

That page has my name and home phone, labeled as such. Below that, is "Please call in case of an emergancy:" and a list of my husband's and parents' names,numbers, and their relationship to me.

My contacts in the PIM also have their relationships listed,just in case my immediate family is unavailable.
I also keep the Medic-Alert card in my wallet. In fact, it is over my DL. I figure,sooner or later,someone will look for that and spot the card with my info. Kind of a back up for the bracelet.