4. Implanted Headphones
In 2013, Utah Grinder Richard Lee had a pair of magnetic "headphones" implanted into his tragus (that's the cartilage-y bit of your ear over the opening). Using a specialised necklace to create a magnetic field, the implant can vibrate and play sound into his ear that only he can hear. Whilst it's handy to be able to listen to music without blocking out ambient noise such as traffic, the implant is much more than a fancy iPod. Lee, who is gradually losing his sight, uses the technology to augment his senses and even echolocate like a bat. Although it is still in its early stages, with power supply being the main issue, the technology, which works by electromagnetic induction, could be used to enhance hearing, connect to communication devices, link up to GPS and, yes, secretly listen to music.