On today's Songcircle, we celebrate the mighty Joni Mitchell - quite possibly The Greatest Singer-Songwriter Ever - with incredible, rare and unreleased recordings from throughout her career, as well as a live preview of tomorrow night's performance at North Portland's Mississippi Pizza, "For the Roses: A Tribute to Joni Mitchell". Concert producer Rachael Rice and PDX folk-rock hero Dan Haley will discuss the show and the artist, and perform their songs from the event.