There was more to John Cage (1912-1992) than his famous silent piece, 4'
33". He brought an appreciation for ambient sound and randomness to the
realm of music, and he pioneered the use of electronics and
non-standard instruments in the modern classical milieu. For example, he
liked to entangle various objects between the strings of a piano, to
generate percussive clicks, odd buzzing or dampened tones. While some
dismiss his compositions as inaccessible to the common ear, many of his
pieces are actually quite pleasant for those with the patience to find
them. We have dug up this little gem for you, from his Sonatas and
Interludes for Prepared Piano:
Wikipedia article: John Cage