The nail violin is a musical instrument which was invented by German violinist Johann Wilde in 1740. The instrument consists of a semicircular wooden soundboard, approximately 1.5 feet (46 cm) by 1 foot (30 cm) in size, with iron or brass nails of different lengths arranged to produce a chromatic scale when bowed.

A waterphone is a type of inharmonic acoustic tuned idiophone consisting of a stainless steel resonator bowl or pan with a cylindrical neck and bronze rods of different lengths and diameters around the rim of the bowl. The resonator may contain a small amount of water giving the waterphone a vibrant ethereal sound that has appeared in movie soundtracks, record albums, and live performances. The instrument was invented, developed, and manufactured by American Richard Waters (1935–2013).