When I got to my day job today, I told my colleagues that I'd picked up my new copy of XP. When I told them of my latest bright idea about having two separate feeds, one of them suggested that I use a Frame Server. What that would do is take any video source and set up a dummy continuous dummy AVI file that can be fed anywhere. He suggested that I use AVISynth. That way, I could feed the same feed to a Windows Media Encoder and an MPEG4 encoder. The MPEG4 encoder would be a little more Mac-friendly, for those Mac users who don't want to use the VLC Player to watch the Windows Media feed (which would be beyond me - it's a better product and it's free). The idea would be that most PC users would watch the WMV feed, the Mac users would watch the MPEG4 feed through Quicktime, and the Linux users would watch either through VLC.
Anyway, I will work on it tomorrow afternoon and evening, as I'm still at my day job at ten after midnight and I have to be back here before 8am.