I've used it far more often to report things to law enforcement. Wreckless drivers usually get called in by me. I also have reported dogs running loose, and other unusual activities i have witnessed in my thousands of miles of riding.

I NEVER go on a ride without the cell phone and a can of pepper spray. Pepper spray is mainly for the dogs but you never know...

It's also very convenient if a ride runs long and you need to call home etc.