For Retrochallenge 2013 Winter Warmup, I've started in with the Reversi64 development. Here's a rundown:
Reversi64 is (will be) a networked two-player game of Reversi for the Commodore 64. It uses the Flyer Internet modem for communications. Once it's complete, I hope to roll it out for a couple of other Commodore platforms, including the Commodore C128 (in native mode), PET, and VIC-20.
My goal is to have a working prototype by the end of the month.
I've set up a website for tracking Reversi64 progress, including a dashboard of issues that I'm wrestling with, and potential solutions. It's at:
http://reversi64.weebly.com
Some more screenshots and blog entries to come.
Onward!