Atari800MacX is a Macintosh OS X Port of David Firth’s Fantastic Atari 800 Emulator. It features 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.
Atari800MacX is now a Universal Binary, and will run natively on Intel Macs. Requires OS X 10.3.9, 10.4 or 10.5.
Download: Atari800MacX 3.9.0