I've been meaning to blog about RoadID for a while. As longtime readers of this blog know (thanks to all four of you, especially my mom!), I run and bike on occasion. I have a long standing paranoia, though, of being found dead or injured on the side of the road, and first responders not knowing who I am or how to reach my family.
So, to address this concern, I always wear a RoadID (usually on my ankle because it's out of the way). These are bracelets with your emergency info engraved on them. They have a few different varieties (e.g. one that you can lace into your running shoes). I now have one for China and one for the US. They're inexpensive and well-made -- I whole-heartedly recommend them to anyone who runs or bikes.
(As a side note, when I'm on the road or vacationing, I usually slip a note with my name and hotel info into my pocket. It's not as durable, but it's better than nothing.)