Stringed instruments have been around for centuries, but nobody's figured out how to keep those strings in tune — until now. The breakthrough introduced at CES 2010 is called the Evertune Bridge, with individual springs constantly pulling against each string at precisely the correct tension to keep each note the same ... indefinitely.
It's hard to see the inner workings of this miracle machine, but in our hands-on encounter with two guitars rigged with the Evertune Bridge, each string stayed in tune no matter what we did. It not only works on guitars, but any stringed instrument such as a piano or banjo. This is brilliant. Look for it on guitars everywhere within a year or two.