Few guitars are as radical as the Gittler guitar. It’s an all-metal (titanium!) exo-skeleton which is mostly the neck — which itself mostly consists of the frets. There is no fretboard. An older version of the guitar was featured long ago in The Police music video “Synchronicity II.”
These are instruments (like the Klein) that polarize — I find you either love them or hate them. They certainly are portable and indestructible. And the ultimate in minimalism. As are most guitars not made of wood, they tend to sound best for modern, heavily-processed tones.