What I would really love is an FPGA implementation of the Atari 8-bit computer series. I had one when I was a child and it was awesome! Very underrated computers they are.
As for the OS-9 part, I was under the impression that CD-i didn't perform very well at all... even the most basic 2D-games where struggling in the machine. I'm not particularly fond of that ehmm... piece of crap. I gave mine for free some weeks ago.