The Musician's Dice
From J S Kingfisher's Musician's Dice website: "The Musician’s Dice are patented, glossy black 12-sided dice, engraved in silver with the chromatic scale. They can be used in any number of ways – they bring the element of chance into the musical process. They're great for composing Aleatory and 12 tone-music, and as a basis for improvisation – they’re really fun in a jam session. They also make an effective study tool: they can be used as 'musical flash cards' when learning harmony, and their randomness makes for fresh and challenging exercise in sight-singing and ear training. Plus, they look really cool on the coffee table, and give you a chance to throw around words like 'aleatory.'"
For more information on the Musician's Dice and Chance Music in general, and to hear some music made with them, please visit musiciansdice.com.