==> SIO2PC, by Nick Kennedy

From the SIO2PC home page:

SIO2PC is a hardware & software package interfacing the 8-bit Atari to PC
compatible computers.

The original idea was to have the PC emulate Atari disk drives so Atari
programs could be stored on the PC's hard (or floppy) drives.  It turned out
to be quite successful.  About 95% of my work was in the software, but a
hardware device to convert logic levels was also necessary.  This device is
now commonly referred to as an SIO2PC cable.

Features:
  -  Emulates 1 to 4 Atari disk drives
  -  Store your Atari files on PC hard or floppy drives
  -  Boot from the PC, real drive not needed to start-up
  -  No software or drivers required for the Atari;
         no conflicts: use your favorite DOS
  -  Twice as fast as an Atari 810 drive and more reliable
  -  Co-exists with real drives in the Atari daisy chain
  -  Compatible down to the hardware level: use sector copiers, etc.
  -  Print-Thru captures Atari print-out and routes to PC's printer
  -  Convert Atari files to PC files and vice versa

http://pages.suddenlink.net/wa5bdu/sio2pc.htm

Another source for various SIO2PC cable design plans is Clarence Dyson's page
at http://www.wolfpup.net/atarimods/

Another (Czech language): http://raster.infos.cz/atari/hw/sio2pc.htm


==> Atari Peripheral Emulator (APE), by Steven Tucker

David A. Paterson writes:
"Steven J. Tucker took SIO2PC one better and wrote new software.
The Atari Peripheral Emulator (APE for short):

- lets your PC act as high-speed drives.
- It lets you print to your PC printer.
- And it lets you use your PC modem on the 8-bit."

http://www.atarimax.com/


==> Sio2OSX, by Mark Grebe

Sio2OSX is a peripheral emulator for the Atari 8-bit computers that allows
the Atari computer to use an OSX based Macintosh as a disk drive, a cassette
drive, and a printer. Sio2OSX performs functions similar to APE or SIO2PC on
Windows based computers.

http://www.atarimac.com/sio2osx.php