Recently I discovered the first video below by Richard Lainhart, performing Olivier Messiaen's Oraison for six Ondes Martinot (1937) on a Buchla synthesizer controlled by a Haken Continuum Fingerboard. The Ondes Martinot is an early electronic instrument, a cousin of the Theremin if you will. Messiaen used the instrument in several of his works. However, it is difficult to get six of them together in one place, so this piece is rarely heard.
Rarely heard in this version, anyway. During World War II, Messiaen was part of the French army; he was captured and sent to a German POW camp. There he composed his most famous work, Quartet for the End of Time for the only instruments available: clarinet, violin, cello, and piano. Messiaen recycled Oraison to create the fifth movement of the quartet, 'Louange à l'éternité de Jésus,' featuring the cello and piano.
Below are both versions, for comparison.