But with their hardened earpieces and stiff bands, most aren't all that great when you're in need of a solid night's sleep. London-based startup Kokoon has designed a pair of headphones equipped with electroencephalography (EEG) sensors and an emphasis on comfort, designed to keep you snoozing until the early hours and then wake you up with feedback on just how well you slept.

Kokoon says that high-tech pillows and sports shoes provided the inspiration for its comfort-oriented, Bluetooth headphones. They are designed to nestle into the natural contours of the skull and store all the electronics inside the band to keep the earpieces nice and slim. The earpieces also feature gel cushioning inside to serve as a mini-pillow for the ears. 

Additionally, the team has developed custom EEG sensors that sit inside the headphones. These monitor the tiny voltages in the brain of the wearer as they drift off to sleep and relay data to a companion smartphone app. Using special algorithms, the system is then able to detect when the user is asleep, lowering the volume and canceling out external noises so as not to wake them up again.