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z26 -- An Atari 2600 Emulator

Altirra is designed with emulation quality in mind, sometimes over speed and polish. It's designed as a system emulator and debugger instead of a games machine, so there is some setup involved.

Hataroid is an Atari ST emulator for Android based on Hatari .

Javatari is a multiplayer Atari 2600 emulator written in pure Java with no external libs. Just open it! Needs Java 6 or greater and Atari ROMs.

The ProSystem Emulator is an Atari 7800 emulator for the PC and Windows OS. The emulator was written in C++ using the Windows API and DirectX. It emulates the Atari 7800 NTSC and PAL TV standards.

jGameBase is a fully-­featured retro-gaming emu­lator frontend and game database utility. It is a sister app­lication to the Windows program GameBase (without "j"), the official frontend for the GB64 Collection.

PCE is a collection of microcomputer emulators. At the moment it contains three emulators:

Windows port of Atari800 based on the original Atari800Win v2.5c sources.

Hatari is an Atari ST/STE/TT/Falcon emulator for GNU/Linux, BSD, Mac OS X, Windows and other systems which are supported by the SDL library.

This is the the Macintosh OSX Port of David Firth's Fantastic Atari 800 Emulator. Ported is the SDL version of the Atrari800 emulator to Mac OSX, and added a full native Cocoa interface, including Preferences, Menus, File Associations, Help and more. It does not require libSDL to be installed separately, but includes it within the application package. It does however require ROM image files from the original Atari systems, which are not included.