Genesis Plus GX is a Sega / Mega CD, Genesis / Megadrive, Master System, Game Gear and SG-1000 emulator developed by eke-eke. The author claims the emulator has accurate emulation and 100% compatibility with Sega Mega Drive, Mega-CD, Master System, Game Gear, and SG-1000 games. It also has preliminary Pico emulation. The emulator was originally based off Charles MacDonald’s Genesis Plus 1.2a. For Mega-CD games, ISO + WAV, BIN + CUE and ISO + OGG formats are supported; ISO + MP3 is not supported.
Full details http://wiibrew.org/wiki/Genesis_Plus