A couple of decades back, Finland offered a gun turn-in and ammunition exchange; some cached ammo, including WWII German panzerfaust antitank weapons had explosive warheads and were becoming unstable, and worse, their rocket propulsion charges could fizzle. And so the great turn-in was announced. And in one district, was a pretty interesting success.
A local farmer pulled up in front of the supply building on his tractor, towing a WWII German Flak 36 88mm anti-tank/ anti aircraft gun. And the clever Germans had sometimes used them as ground-to-ground artillery.
The helpful farmer also had a small wagon in tow, with several dozen high explosive rounds, and about 50 rounds of armor-piercing antitank rounds. They had to think real hard about what to offer him in exchange, but eventually something was worked out involving an antitank recoilless rifle.
The gun he towed in? It has a nice home in the Finnish national military museum now.
