This is a quite interesting Easter egg not very many people know about. It is mainly included in games whom Songwriter Kazumi Totaka was involved in the game's production. The song is very well hidden in the games.
http://www.youtube.com/watch?v=eLMAgcGA8Dw (http://www.youtube.com/watch?v=eLMAgcGA8Dw)
http://www.youtube.com/watch?v=biLfTqQA5T8 (http://www.youtube.com/watch?v=biLfTqQA5T8)
http://www.youtube.com/watch?v=tBO8EZSNH3A (http://www.youtube.com/watch?v=tBO8EZSNH3A)
http://www.youtube.com/watch?v=nEWYsxa5udM (http://www.youtube.com/watch?v=nEWYsxa5udM)
Thoughts?