Wikipedia
Wzonka-Lad is a Nintendo Game Boy emulator for the Amiga series of computers.
Wzonka-Lad was written by Ville Helin in the 1990s and 2000s in 68020 assembler. Wzonka-Lad only emulates the Game Boy processor and hardware interaction - it does not contain the Game Boy ROM or any games. These must be acquired separately. At the end of its life, Wzonka-Lad dropped its shareware status, and became GPL software.
The reason why Wzonka-Lad came to be was Virtual Game Boy, a Game Boy emulator written in C ported to Amiga. It ran so slowly on Amiga hardware that Helin decided to write one faster in ASM.
A common misconception of the name "Wzonka-Lad" is that it means "game boy" in Finnish. This is not true - "wzonka" is a nonsense word invented by Helin, and "lad" is simply the English word "lad".