Gustav Rail Cannons
World War II saw both sides of the conflict attempt to build ever more elaborate and powerful weapons to try to gain an advantage. One of the crazier designs that came out of this period was the German Gustav Rail Cannons, a pair of cannons that were bigger than any other ever built. They weighed an incredible 10,000 pounds and could fire at targets 90 miles away.
M-28 Weapon System
Often known called the Davy Crockett because of its unusual shape, the M-28 Weapon System looks and operates much like any other mortar. The only different is that it fires small nuclear bombs rather than traditional explosives. The portable nuclear device had the power of 20 tons of TNT and would be able to decimate any battlefield, though it was wisely never used in combat by the US army.