Made by some kids at the University of Nottingham in the UK:
Pretty risky move in the UK. Observe at 1:47 when the crazed smoke ring gunman lets loose.
I purpose filling the box with a mixture of concentrated cigarette smoke and farts, and essentially firing cancer and stink directly at enemy lungs.
The University of Nottingham is in the hometown of Heckler & Koch. If HK made a smoke ring vortex cannon they would only sell it to law enforcement for copious amounts of money, and scoff at the civilian market worldwide.
You can check out this bigger, more grown up version of the Cannon with a guy that’s just a bit more excited than he should be.
Hat tip: Stuart