An illustration from the Wheel of Time fantasy series by Robert Jordan, the Dream Ring is a ter'angreal- an artifact that can manipulate the One Power. This particular ring can, if touching a person's skin, allow that person to enter the World of Dreams, or Tel'aran'rhiod- a place where the mind is supreme, and death awaits the unwary.
In The Dragon Reborn, Chapter 21, the ring is described as follows:

"... a ring carved from stone, all flecks and stripes of blue and brown and red, and too large to be a finger ring.
... The ring certainly looked like stone, but it felt harder than steel and heavier than lead. And the circle of it was twisted. If she ran a finger along one edge, it would go around twice, inside as well as out; it only had one edge."

Second View

Original Model

The shape of the ring was conceptually simple, basically a three-dimensional Möbius strip. The difficult part of the design was creating the surface texture. I used a multilayered texture with a matching bump map that allowed for the red and blue flecks to be apparent and yet not appear unnatural. I originally created the ring using Meshwork and Strata 3D while still in high school. In the spring of 2007, I recreated the ring in Form-Z, reusing the original textures I created but making a higher quality model.

Sculpey Models -
Still Life

Painted Sculpey
Model

I also made the ring in physical media. Using Sculpey modeling clay, I created multiple rings of varying size. At the request of my sister, I finished the smallest one, which was less than 1.25" across. The color was not quite right, but my sister liked it. The three larger rings were never finished, but I did make an interesting still-life photo with them.