Robert Howsare, a student from Ohio University, has built a rudimentary yet interesting drawing machine out of two old turntables and some wooden planks.
The home project, which cost a mere $50 to put together, is simply known as the "drawing apparatus." The drawings produced by the machine are surprisingly attractive, with random asymmetrical lines and patterns as shown in the below video. In fact, I personally found watching the rotating turntables and planks entertaining, and even therapeutic to some extent.
So before you throw out any outdated but still functional hi-fi components, you may want to consider the ways they could be repurposed first.