I love my RoadID, I have the velcro sport in purple. I wear it biking and snowboarding, especially if I'm out with friends and not family. I'm single and have no siblings so someone would have to call my parents and I'm not exactly thinking to pass out my mom's phone number to my friends when we go outdoors! This past Christmas I got RoadID bracelets for my mom and her boyfriend, they are avid hikers and he's also done some mountain climbing in the Cascades and rides the STP. I also got one for my friend that I always do outdoor sports with, I'd probably know to call his brother if he were in an accident (punk keeps trying out the beginner snowboard park without a helmet!) but I wouldn't be able to provide the hospital with his insurance info or anything. Next year, their stocking stuffers will be a renewal of their RoadID account subscription!
I also try to keep my drivers license and my insurance card in my pocket (if it's a sport with pocketable clothes). I want to make sure the responders know right away they can take me to an appropriate hospital and I always jokingly tell whoever I am riding/boarding/hiking with for the day that if something happens please contact my insurance in 24 hours. Silly, but it makes me feel better.
A close friend of mine went snowboarding for only the 2nd time with coworkers that didn't know her well outside of work. They encouraged her to take a higher ski lift before she was ready and didn't know she was afraid of heights. She hyperventilated and conked her head falling when getting off the lift. She continued on anyway and passed out about a quarter of the way down the run. Ski patrol had to toboggan her down the mountain and because she had hit her head she got an ambulance ride to the nearest hospital with only her coworkers aware of what was going on and with no idea of who to call. Turned out she was fine and started tweeting pictures of herself strapped to a backboard in the hospital, but until I saw those tweets no one contacted her roommate or her parents. Even if you don't go for a RoadID or forget to wear it (I'm trying so hard to get in the habit!), just having everyone in a group leave a contact name and number on a list in the car can be helpful to make sure the right person gets contacted.
2011 Trek Lexa SLX "Silver Surfer"
1998 Specialized HardRock AX FS