RetroArch - RetroArch is a frontend for emulators, game engines and media players.
melonDS - A Nintendo DS emulator with support for commercial games.
Mesen - Mesen is a NES/Famicom emulator and NSF player.
Snes9x - Snes9x is a portable, Super Nintendo Entertainment System (SNES) emulator.
nds4droid - nds4droid is a free, open source Nintendo DS emulator written for Android smartphones.
BSNES - bsnes is a Super Nintendo (SNES) emulator focused on performance, features, and ease of use.