In 1975 artists & musicians Brian Eno and Peter Schmidt collaborated on a project titled Oblique Strategies. Inspired by the readings of I Ching, the two published a set of cards used to generate ideas and break routine thinking patterns.
While born out of a studio context, Oblique Strategies translated equally well to the music studio. For Eno, the instructions provided an antidote in high-pressure situations in which impulse might lead one to default quickly to a proven solution rather than continue to explore untested possibilities: “Oblique Strategies evolved from me being in a number of working situations when the panic of the situation—Particularly in studios—tended to make me quickly forget that there were others ways of working and that there were tangential ways of attacking problems that were in many senses more interesting than the direct head-on approach.”
—Brian Eno: Visual Music, Christopher Scoates
Now on their fifth edition, Oblique Strategies have been published in English, French and Japanese. Each edition changes slightly, adding or removing different cards. If you're interested in learning more, Gregory Taylor has put together a fine website documenting the editions and pulling together some more information about the deck.