Introducing ABall... a DIY buttonless trackball! : r/Trackballs
DIY open-source trackball similar to MTE - deskthority
DIY Trackballs
SparkFun Electronics on Twitter: "A billiard ball finds a new home in this custom trackball mouse project. #DIY https://t.co/lJOHkI4Jps https://t.co/jLvFMIkkdS" / Twitter
Ultimate GREEN DIY Trackball Mouse From Junk : 10 Steps (with Pictures) - Instructables
Make Your Own Mouse Trackball : 4 Steps - Instructables