Clark was recently pulled up at a red light with his children when he heard the faint sound of a siren. As the light turned green, some motorists who couldn't hear the wail growing louder started taking off. Those that did almost had a collision with an approaching fire truck. It seems that technology has caused unexpected problems for motorists -- between people driving while listening to iPods, chatting on their cell phones or blocking out exterior noises with massive sound systems. Sometimes Clark thinks drivers are in a nuclear arms race to see how many speakers they can pack into their vehicles! But what if you could silently alert people to the presence of oncoming emergency vehicles? An Illinois company called Federal Signal Corporation has come up with a device called "The Rumbler" that's being tested in New York, Florida, Pennsylvania and Virginia. This noiseless siren system emits low-frequency vibrations that make your car shake. You can feel it from 200 feet away. Clark also read in The Washington Post that D.C. police are using this system in four dozen patrol cars and plan to install Rumblers fleetwide. Technology started the problem of making drivers oblivious with loud music and cell phones; now technology is trumping technology to make the roads safer for emergency vehicles and you!