Astrodice by Wessex Astrologer
These beautifully responsive acrylic dice tumble easily, and were always popular when we had them on the stand at conferences. They come with a velveteen bag so are easy to stash in your bag or pocket ready for that impromptu reading. Also a fabulous resource for astrology students just learning the basics - test your knowledge by interpreting the dice without referring to the booklet, then check your answers.
Also used by tarot readers for added insights.