Want your guitar to stay in tune, but can't afford a Gibson Robot Les Paul? EverTune has a product in the works that will help. It won't help you switch tunings, or tune the guitar for you like Gibson's effort, but once you've tuned a guitar with an EverTune bridge, it apparently stays tuned forever.

There's nothing digital on board, just "simple mechanical principles". As your strings or tuning posts loosen, an adaptive spring-tensioner compensates, and keeps tension locked exactly to where you set it. This means it supports any non-standard tuning you desire.

EverTune is in talks with guitar manufacturers to include its bridges on new guitars, and will also be available in kit form to retrofit to your favorite axe. Interested parties can sign up for updates at evertune.com/contact.

Image via DVICE