At the extreme end of the spectrum, this may involve manufacturing products in batch size 1 under industrial mass-production conditions -- that is, manufacturing unique items on a conveyor belt.
While the underlying mechanisms are still poorly understood, it has been suggested that the mirror neurons play a major role in mass hysteria outbreaks.
Alternatively, a chemically inert reaction mass can be heated using a high-energy power source via a heat exchanger, and then no combustion chamber is used.