Headphones are dangerous, simply because they block out everything else.  Yet everyday, millions of people drive, bike, scooter, and operate machinery with headphones blaring.

But what if you could hear what's going on and still listen to the audio?

Bethesda, MD-based David Nghiem is one person trying to solve this riddle.  Nghiem noticed that municipalities have been banning headphones while driving or biking, for obvious reasons.  So Nghiem's company, Conduit, is focused on developing bone-conduction, 'off-ear' headphone technology.

If you haven't tried bone-conduction, a little warning: it's a weird feeling.  The sound is actually transmitted to your brain even though the headphones aren't covering your ear canal.  In fact, you're canals are free to hear other things, as long as you don't crank up the volume too high.

But wait: how the f^%* does this all work?