I carry a wallet with quite a few "official" and not so official I.D.'s and "unofficial I.D." includes a brief medical history on microfiche. Yes, I know that I am dating myself and yes, I realize that there MAY be some here who are wondering what "microfiche" is.

I quit carrying "dog tags" when I retired from "active duty" and they are now great momento's for my wife and DD2 who now possess the two pairs that I had used.