I went down the tunnel of using SDR to recieve those transmissions, and share them online.
Then I went a bit further.
What if you could transcribe the broadcasts into something like a text feed? What if you could add location information somehow to monitor where things were going on in your region? Could you use AI to somehow organize the data into a more useful format?
What if this data was valuable? Maybe you could sell this as a service? Who would buy it? Public safety organizations? Hospitals? News organizations?
I spent a few days worth of freetime figuring out how you'd do someting like this, and got to a place where I figured it was conceptually possible.
Then somewhere in my googling, I stumbled across this site: http://citizen.com/ - and realized that someone had already turned my idea into what looks like a pretty mature product.
Ahh well. I'm sure my billion dollar idea will come later.
In the meantime, I'd still like to mess with SDR at least so I can know what's going on around me next time there's a fire or other public safety incident, before it gets reported on.