One of the modern classical guitar's biggest strengths is also one of its biggest weaknesses. The instrument depends on an equal temperament fretboard system that has lent itself to brilliant repertoire and ease of production, yet this same fretboard system does not lend itself to perfectly tuned notes and tuning systems not found in Eurocentric classical music. Many guitarists and luthiers have sought a fretboard system that marries the benefits of equal temperament with the rich possibilities of just intonation and other tuning systems. This paper presents two new fretboard designs and discuss their role in the history of guitar fretboard construction. Our first design is a fully functional fretboard made from the popular toy 'Legos' and solves many of the problems that previous designs had, including ease of use and production, affordability, and versatility. Our second design is a one-string prototype for an automatic (automated) fretboard that would allow performers to switch tuning systems instantly at the press of a button.