PG is releasing a neat 25th anniversary edition of SO
http://petergabriel.com/so25/
One of the discs is called "So DNA" and has early versions of the final tracks and some unreleased heard stuff. Here's his engineer discussing - I like the funky bass line of the track "Courage" at 05:10
http://www.youtube.com/watch?v=Yudjbg8p9hI
