Game Gear emulators

specialized section of the Wii Shop Channel and Nintendo eShop providing games from past systems, mainly via emulation

RetroArch is a free and open-source, cross-platform frontend for emulators, game engines, video games, media players and other applications. It is the reference implementation of the libretro API, designed to be fast, lightweight, portable and without dependencies. It is licensed under the GNU GPLv3.

Mednafen (My Emulator Doesn't Need A Frickin' Excellent Name), formerly known as Nintencer, is an OpenGL and SDL multi-system free software wrapper that bundles various original and third-party emulation cores into a single package, and is driven by command-line input. It is distributed under the terms of the GPL-2.0-or-later license. Certain emulation cores of Mednafen have been ported to RetroArch/Libretro.

OpenEmu is an open-source multi-system video game emulator designed for macOS. It provides a plugin interface to emulate numerous consoles' hardware, such as the Nintendo Entertainment System, Genesis, Game Boy, and many more. The architecture allows for other developers to add new cores to the base system without the need to account for specific macOS APIs.