I'm wondering if there is a more perfect male-female duet in the annals of rock than Tom Petty and Stevie Nicks. They really meld. In 1981 they released two songs together, the Grammy-winning chart topper Stop Draggin' My Heart Around on Stevie's debut solo album and Insider, a deep cut on Petty's fourth album, Hard Promises. Both so good, but I think I'd have to pick Insider if I had to take just one. Have a listen: