Made some progress today. got mysql up and running the unraid server, linked my xbmc database to it, and now any xbmc install will be synchronized to it. So now I can start a movie in the living room, pause it, and finish where i started in the bedroom (or garage, or wherever else i have a tv set up). It will also sync up thumbnails, watched status, etc.
The only thing left to do is populate the serve with data. I'm trying to make sure all my media is organized and complete before I copy it. I also just need to set up a remote control for the htpc, just waiting for a dongle for that.
I'll post some final pictures once it's all finished and in place. I'm just using old computers I had in the garage for now. At some point I'll update them to something that actually looks nice in the living room.