A Chaos Machine is a massive collection of tubes, tracks, motors, and other widgets that can be used to move marbles around a layout that you build yourself. It’s a bit like LEGO, only with marbles racing around. The main components of the machine are produced in kits from Chaos Toy (http://www.chaostoy.com/).
The machine is set up as a basic framework by the Chaos Wranglers, then participants (Mechanics) begin to build tracks, install ball lifts, add stunts, and generally have a good time learning and problem-solving. Over the years, more sets have been added, so the machine grows larger with each installation.