They are called Q-jays, cost EUR395 and are, for now, the smallest headphones in the world.
Notwithstanding all that, you need not worry they would disappear into your ear and disappear in the depth of your ear canal. They still very much retain the traditional level of comfort and quality of the Jays branded products. Besides, the fact they may be the smallest is not what matters most - where Q-jays take a big step ahead of the competition is the a unique option to change the headphone cable.
Headphone cable is the most frequently damaged part of any headphones, being frequently pushed into bags or pockets. In this instance, the cable is simply unscrewed from the main body and replaced with a new one. So, music never stops.