Many years ago, I developed WinBoard plugins for autoplaying unusual chess hardware on the Free Internet Chess Server. Here are the results of these efforts.
The Novag Sapphire II and some other Novag models came with a serial port. The port was designed for interfacing to a PC or Novag's auto sensory board. I repurposed it for communicating with WinBoard. I managed an account on FICS named SapphireII, where I played my own Sapphire II. It achieved ratings of around 2000 in blitz and 2200 at standard. Here are the sources for building the WinBoard shim.
My first project was even more unusual. I owned an Apple MessagePad 2000, to which Joachim Bondo had ported John Stanback's old SCP program, calling it Deep Green. Because the MessagePad used a 160MHz ARM, the program was surprisingly strong for a handheld, about as strong as Fidelity's Elite Avant Garde/Excellence. The Newton's programming system had the unusual feature of being decompileable, so I could examine the source and develop my own remote control interface, called AutoGreen. I then played it on an FICS account named NewtonChess, where Deep Green achieved ratings of around 1850.
Here are the sources for historical interest.
When I bought one of the original 200MHz ARM iPAQ PocketPCs, I was disappointed to find there were no strong chess programs available for it. In response, I wrote PocketCrafty, a simple PocketPC user interface and POSIX emulation layer for Dr. Bob Hyatt's program Crafty. For a few months it was the strongest player available on a handheld. Then Richard Lang ported his old Roma program to the PocketPC (Chess Genius}, and I lost interest.
One bonus of writing your own program is that you can include an interface for playing it remotely. Here is the WinBoard shim required to play it in WinBoard. One must keep the iPAQ in its cradle, and enable the xboard option in PocketCrafty's preferences.