The designers at Studio Banana Things have recently launched ear-free headphones, named BATBAND, that sit around the back of your head, instead of covering your ears.
Description from the designers
BATBAND is an elegant piece of sound technology allowing you to listen to your private soundscape as well as the world that surrounds you.
Human-centered design meets technology delivering a high fidelity acoustic experience via an innovative bone conduction system.
BATBAND works via bone conduction, consisting of transducers that emit sound waves perceived by your “private” inner ear, thus freeing your “social” outer ear.
Sound waves are transmitted at a frequency that can be conducted through the bones of the skull. Your ears remain free, therefore you get to hear twice as much, without compromising on comfort, quality or style.
3 transducers emitting sound waves are incorporated in the product: two touching the sides of your head (temporal bone) and one at the back of your head (occipital bone). Furthermore, its discreet use means that any vocal content you receive is nearly inaudible to outsiders.