Ok so if you're really sure you don't want to include the Prometheus, which personally I think you should, how about integrating a Picasso 2 on board? Maybe Matze would let you use/adapt his version of the Picasso? I thought that Prometheus worked at least with a couple sound cards as well? And for that matter maybe there's an open source sound upgrade that you could include? At the minimum something like an MP3@64 type device just to decode mp3s? And whether that's an option or not how about putting on a clockport just for fun, that should be pretty simple.