But we here at Hackaday don’t judge based on alternate input lifestyles, and we quite like this billiard ball trackball mouse. A trackball aficionado, [Adam Haile] spotted a billiard ball ...

The moveable sections are attached to the mouse core via a pair of ball joints connected with extendible arms, allowing the surfaces to be adjusted for both position and orientation. The design ...

There, he replaced the wheels on his first mouse design with a rolling ball - the design that became familiar to most end users over the next decades. A similar design had already been tested by ...