Nintendo
DeSmuME is a Nintendo DS emulator.
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Developer: desmume.org
License: GNU General Public License (GPL)
Operating System: OS Portable (Source code to work with many OS platforms)
Dungeon Master Nintendo DS port (for playing DM, CSB and DM2 on NDS).
Developer: dmds
License: Open Software License
Operating System: Console-based Platforms
Spider Solitaire DS; The classic single player card game on the Nintendo DS.
Developer: spidersolitaire
License: GNU General Public License (GPL)
Operating System: Console-based Platforms
Mac Crack Attack is a port of Crack Attack to the Mac OS X platform.
Developer: crackattack
License: GNU General Public License (GPL)
Operating System: All POSIX (Linux/BSD/UNIX-like OSes), OS X
Daedalus is an established open-source Nintendo 64 emulator for Windows and the Sony PSP.
Developer: strmnnrmn.blogspot
License: GNU General Public License (GPL)
Operating System: All 32-bit MS Windows (95/98/NT/2000/XP), Console-based Platforms
JMario is a side-scroll game, built in Java, based on Nintendo´s Super Mario World.
Developer: jmario
License: BSD License
Operating System: OS Independent (Written in an interpreted language)
Cosmos (C# Open Source Managed Operating System) is a complete operating system built from the ground up in C#.
Developer: Cosmos
License: GNU General Public License (GPL)
Operating System: platform independent