Iner Souster makes experimental musical instruments. His stringed instruments are often made from salvaged materials, and are art works in themselves.

Antony Charles Tomlinson, the luthier/artist behind British Custom Guitars has been designing and building custom guitars since the 1980s. His instruments are unique, and some of them are more like pieces of art than instruments.

Yuri Landman is a Dutch experimental luthier, musician and comic artist. He has built electric zithers, electric cymbalum, electric 3rd bridge guitars, and electric Koto. Yuri started making instruments out of wood salvaged from furniture and door frames. He used hardware salvaged from old guitars as well as audio equipment, printers, and other electronic stuff.

Atlansia is the brand of Japanese guitar maker and genius inventor N. Hayashi, and has been active for at least 40 years. Also makes guitar making machinery. I cannot find any distributors of the Atlansia brand outside of Japan.