A harp tuned to C-sharp major has all its pedals in the bottom position. Because all the strings are then pinched and shortened, this is the least resonant key for the instrument.
The Allegro de concierto by Spanish composer Enrique Granados is written in C-sharp major. Canadian composer and pianist Frank Mills originally wrote and performed his instrumental hit "Music Box Dancer" in C-sharp major; however, most modern piano editions have the piece written in C major.
Louis Vierne used C-sharp major for the "Dona nobis pacem" of the Agnus Dei of his Messe solennelle in C-sharp minor.