The Man deserves a thread by now, so...
Astor Piazzola was a 20th century Argentinian tango composer and bandeneon virtuoso (think of a longer yet more compact accordian) who took the drab old world tango style and turned it on it's ear by composing atypical tango arrangements in an orchestral style.
His music is quite a departure of what one preconceives as being tango: vigorous, melodramatic, dance-oriented music and is instead very soulful, spiritual, almost surreal, great for those existential crisis or indulgent depressive periods.
His work has been covered by the likes of The Kronos Quartet and Yo Yo Ma, and the latter's The Soul of the Tango: The Music of Astor Piazzola is a fantastic interpretation of some of Piazzolla's more famous pieces by one of the world's greatest cell o players. And Piazzolla's own album Tango:Zero Hour is one of his best, released just 6 years before his death in 1992.