I am not a frequent traveller. On my occasional rambles, I do encounter inspiration for gaming. Last fall, my wife and I visited the somewhat-nearby college town of Athens, GA. Mostly a pilgrimage for artifacts of my favorite band from adolescence, R.E.M., we unexpectedly encountered a bit of military history from the era of VSF.
Keeping watch over a town square, this beauty was an authentic failure of the military imagination. The accompanying documentation tells the whole story. There’s a Wikipedia page, too, which fleshes things out a bit.
A replica in miniature would be a straightforward scratch building affair, intended for either the VSF or Warhammer milieux. When fired, I imagine it would have a certain chance of inflicting double damage or flying wild and potentially hitting friendly troops…