I also use this site:
http://www.mediguard.org/
You can print out a list of all your meds and any health conditions you have and keep it in your wallet. You can also subscribe to email which informs you of new alerts about medications you take and if you are at risk of any interactions because of them. I list all my vitamins and supplements on my list too. My car insurance company always provides me with two cards, so I keep one in the glove box, and one in my wallet. This is another good way for the hospital to find out who you are and whom to contact.
Sometimes when I'm shopping I do not have my wallet with me, but I usually DO have my phone with me. I just keep my charge card in my pocket. Many people are aware of ICE so if they come upon an accident they may try to search your contacts. Of course they can try your speed dial contacts too. Also, when I'm shopping I usually have my coupon holder, so I have an old insurance card and contact information and my medline list in there. It has a pocket that is visible from the outside, so hopefully someone could find that info.