well Chopin could only write for solo piano as oppose to Thomas Ades who has good Operas, Ballets, Orchestral music, and piano music.
Not entirely true..
He composed 80 opuses, which all involve the piano. Not all are for SOLO piano however:
In addition to his solo piano output, he composed two concertos for piano and orchestra, Opp. 11 and 21; a sonata for cello and piano, Op. 65 (Chopin's last composition published in his lifetime); a polonaise with orchestral accompaniment and one for cello with accompanying piano; one krakowiak for piano and orchestra, an Allegro de concert (possibly the remnant of an incomplete 3rd concerto), a Grand Duo on themes from Giacomo Meyerbeer's opera Robert le diable for cello and piano; and 19 Polish songs for solo voice with accompanying piano.
Did I miss any other collaborative works?