This is a model of the Umbilic Torus, which is a very fun shape to show people. It has only one side and one edge. I've posted a simple java file showing how I created the model.
The shape I've provided is not an exact Umbilic Torus because the cross section is not a deltoid. I did this for asthetic reasons and to make the printing come out nicer. I intentionally made the edge have a finite width for 3D printing. Also in my code you can modify the radius of curvature of each of the sides of the cross section.
I hope you find it enjoyable!
