Super-battleships that their navies could not build

What is the most ridiculous warship plan, excluding the Tillman designs?

Choose among the various Soviet, German, and Japanese super-battleship proposals whose infrastructure, energy, and industrial requirements made construction unrealistic.

Several super-battleship schemes fail the same test, so no single drawing stands out as the obvious choice. Their designers can specify enormous weapons and displacement on paper, but the sponsoring navies lack the infrastructure and energy to produce the ships. A proposed warship must be evaluated together with its industrial system rather than through specifications alone. Feasibility is a strategic characteristic of a design.