Masao Saiki is an 80-year-old composer reaching the debut 50th anniversary in this year.
He is a very famous man in the Japanese music industry, but he posts a works using vocaloid Hatsune Miku to video sharing site Nico Nico Douga from last year. Of course himself does ALL WORK. His nickname in Nico Nico Douga is "Masa-P"(P is a meaning of the producers. Most of Hatsume Miku composers add P to a nickname).
His works are slightly nostalgic. and styles of the old Japanese popular song. However, the evaluation in Nico Nico Douga and Twitter is excellent.