A collection of Arduinos with a small form factor thanks to TinyCircuits has been programmed to implement "undulators", small self-contained circuits that change the characteristics of a modular synthesizer patch over time to help make the sound interesting. Due to the programmable nature of them, random parameters can also be added to the program so the control function is always slightly changing. A recent performance on the system that uses these known as the "Drone Boat" can be heard here: https://soundcloud.com/steven-curtin/tympanum-062218