I was just thinking about smart phones (not smartphones!) and what you could do with the accelerometer in an iphone. Here's an idea for an application that might put it to good use. The app runs on an iphone or some device with accelerometers. When it detects a shock profile that matches what would happen in a crash it goes into "are you okay?" mode and waits for a response. After a few minutes (don't want it to be too soon, you need time to pull your stuff out of the road before you mess with a phone) it calls/messages/emails/twitters with a prearranged message. "Hey, I crashed at this address and I'm not responding to my phone." The crash profile should be something different than just dropping the phone. You could also do something with the position of the phone to report the position of the bike, but that might be less useful. It wouldn't have to be limited to cycling. Other outdoor sports & travel would be easy, as long as you're in cell range. I tried to find this in the iTunes store but as usual it's too goofy for me to navigate.