In 2015 I wondered if a 3D version of a phone app game I played while waiting idly in lines might be as fun as the 2D version. This is my proof-of-concept in Unity using C#. It has been shown to run on iPhone, Android, and Windows. Below are some short gameplay clips that loop:

After launching the game, touch either side of the screen to rotate that direction, or for a non-mobile device use the arrow keys. Most of the C# code I wrote is in the Assets folder.