I think this is a fantastic idea. Spread the word to all riders.
CRADAR is a man-down application that runs on any Android phone.
CRADAR senses when you fall, waits 30-120 seconds (whatever you set it for), and if it doesn't see you move at least 8 feet, sends a text message to one of your contacts telling them you might be hurt. This gives your contact a chance to call you to see if you're ok.
In the text message is a link to Google Maps with your GPS coordinates.
If they don't get an answer, they know exactly where you are, and have the GPS coordinates so other people can find you too.