So you're diving down 41st street rocking out to "Kung Fu Fighting",or you're on the phone figuring out your dinner menu and all of a sudden there's an ambulance right behind you! Where did that come from?

Emergency vehicles have been taking people by surprise since the Model T was chugging around, but now in Denver, they've come up with a solution. Denver Health EMS is equipping their ambulances with subwoofers that shake the ground when the sirens are going off.

The 200 watt amplifiers point at the ground and the frequency they generate is low enough to vibrate everything outside the ambulance. Its just like that kid pulling up beside you blaring hip-hop so loud your teeth chatter. Denver officials seem to think it is making people more aware.

Noble experiment or fruitless effort? I guess we'll find out.