Neil Gaiman.

Via his website:

And our bizarre but oracular word for today is gyromancy – 1557, from M.L. gyromantia, from Gk. gyyros “circle” + manteia “divination, oracle.” “A method of divination by walking in a circle till the person fell down from dizziness, the inference being drawn from the place in the circle at which he fell.”

Lee notes that Rachel practices gyromancy all the time.