John GBA - The GBA emulator is a software program that allows you to play Game Boy Advance games on your computer.
FCEUX - FCEUX is a Nintendo Entertainment System (NES), Famicom, and Famicom Disk System (FDS) emulator.
MESS - Emulates most gaming systems that exist, emphasizing accuracy over speed.
Nestopia - A portable and cycle-accurate NES emulator written in C++
Eclipse emu - Eclipse is a multi-platform emulator of Game Boy Advance and Nintendo DS games.
RetroArch - RetroArch is a frontend for emulators, game engines and media players.