This blog post describes a technical achievement where a fully functional calculator was created within the game Super Mario Bros 3 using Arbitrary Code Execution (ACE). The author combines their passion for programming, math, and nostalgia for the NES to explain the intricate process of developing this calculator. The calculator supports various operations and leverages complex mathematics, but faces limitations due to the NES's hardware capabilities. Detailed technical descriptions and challenges faced during development are provided, catering to enthusiasts of both programming and retro gaming.