A8E: A freeware 800XL emulator for Windows/SDL.
Atari 800 Emulator for Windows: A step-by-step instruction for downloading and playing classic games in Atari800Win PLus.
Atari++: An open source 130XL, 400, 400XL, 800, 800XL, and 5200 emulator for Unix and Windows.
Atari800: An open source 800, 800XL, 130XE and 5200 emulator for BeOS/x86, DOS, Linux, TOS, Unix, Windows, and Windows CE.
Atari800MacX: MacOS X port of the Atari800 emulator.
Atari800Win PLus: Windows port of Atari800 based on the original Atari800Win v2.5c sources.
EMUAPC: A commercial 130XE, 400, 65XE, 800, 800XL emulator for DOS and Windows.
Rainbow: Shareware Atari 400/800/800XL/130XE/5200 emulator for MacOS and Win32.
Rainbow/Mac: A MacOS X port by Richard Bannister of Rainbow.
TOSBOX homepage: A shareware emulator for DOS.
WACKE: Atari 400/800/XL/XE emulator for MacOS.