Looking for the best old school gaming emulator for Mac OS X? Look no further, OpenEmu is an awesome emulator for nearly all of the classic retro gaming console, with full support for Game Boy Advance, Game Boy Color, NeoGeo, NES, Nintendo DS, Sega 32x, Sega Game Gear, Sega Genesis, Super Nintendo (SNES), TurboGrafx 16, and VirtualBoy.