A lot of Wyschnegradsky's compositions made great use of semitonal melodies and harmonies, some of them leading to his own developments in music theory. For instance, he liked to use what he called "ultrachromatic scales," which I still have yet to understand. Needless to say, his manipulation and, sometimes, rejection of equal temperament has led to some pretty interesting sounding stuff. If you want to know what goes on "between" the notes, then Wyschnegradsky's your guy.

What are you listening to tonight?