Read more: 12 Smart Gadgets You Didn't Know Existed Given its $150 price tag when it first launched -- which is worth about $680 today -- the original Walkman from 1979 was quite expensive to buy.

Not so for MiniDisc enthusiasts, many of whom still use a MiniDisc deck at home and a MiniDisc Walkman on the go. Unfortunately, high-end headphones these days often come with Bluetooth ...