Movement
Image source: Four-stoke cycle at Wikipedia.
To my mind, this is a more beautiful Rube Goldberg machine: the internal combustion engine.
Intake, compression, power, exhaust.
So what’s happening here. It needs a spark to get going, just like a message-board community online. And then it keeps cycling, and almost as a side-effect it outputs mechanical motion which goes to the wheels. But another side-effect of the process is that the motion also provides the intake stroke to start the cycle again. It’s self-perpetuating, just you use the energy from breakfast to go and make dinner, and you use the energy from supper to go and get breakfast again.
The impressive thing about the internal combustion engine is really that it keeps going without petering out or blowing up.
The more you start examining it, the more useful it gets as a piece of idea scaffolding.
Once you start thinking in the Otto four cycle manner, you can ask yourself questions about all kinds of systems, online and offline: who is the spark? How does the power output also provide for the next intake? You know, what is the carbaretta of the website.