Just as there is no one-size-fits-all bicycle seat, there is no one-size-fits-all pair of headphones. Of course, the headphones can be custom molded for you (depending on the shape of the ear opening), but this method is time consuming, not to mention expensive. But only if you don't consider Revols wireless Bluetooth headphones, which, like silicone earplugs, adapt to your ears one, two, three. The headphones are a real hit on Kickstarter, where they have already raised well over 1.2 million dollars and thus exceeded the originally set goal by more than 10 times.