jGameBase - jGameBase is a fully-featured retro-gaming emulator frontend and game database utility.
VICE - Bring loops to life with the loop slicer plugin for Mac and Windows.
Stella - Stella is a multi-platform Atari 2600 VCS emulator released under the GNU General Public License...
Frodo - Frodo is a robust Commodore 64 Emulator for the Macintosh.
Javatari - Javatari is a multiplayer Atari 2600 emulator written in pure Java with no external libs.
GameBase - bu22.com - the home of the GameBase frontend and databases.