Here's an idea (albeit a possibly unruly one). Consider how dangerous an ambulance is to other drivers, even though the idea behind it is to save lives. They have to run lights to do their jobs. And in a noisy city (or say with your music up a bit too loud), that can mean possible accidents.
So here's the idea: create a traffic system where ambulances and police officers could turn lights into red flashers as they passed. People would not only have the warning of the sirens coming, but they would also see the traffic light they are at change.
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Already been done here. When the emergency vehicle approaches a signal a device on the vehicle emits code that switches the lights to red in all directions.
Look up a traffic signal preemption device...