Inspired by this GIF, https://media.giphy.com/media/3o7WTN8FmMgK9hrZyU/giphy.gif, and generated from this GIF, https://media.giphy.com/media/l2QZQPdpBznOzxE9a/giphy.gif, note how each circular path is a simple 2D sine wave (look at it from above). Put together, these form a rotating circular pattern. The model is created by stacking the frames of animation one atop the next. See http://bit.ly/t2zspot for the software and more.
Also, try the spinning version: https://sketchfab.com/models/370b66ebb2fa4f4dbb69330d15d88da2?autospin=0.9