Beer Gun
This thing, to put it simply, is a monster of mid-20th century engineering. The Beer Gun looks roughly like a drastically scaled-down version of a M61 Vulcan rotary cannon; while it is light enough to be fired by a person, there’s a handle on the top to grab while firing. The user frankly needs it, given that this thing kicks like a mule. The Beer Gun has six muzzleloading barrels: each barrel can fit one standard-sized can of Budweiser beer from the 1950s (the US Army manual that accompanies each Beer Gun is adamant that only Budweiser is to be used). The firing mechanism is one heavy-duty titanium spring per barrel: once a chamber has been fired, it takes a total of one minute of steady ratcheting with an included jack to cock the spring back. There are no electrical or chemical components to the Beer Gun at all, and all of the mechanical parts are designed to be as rugged as possible.