Charmed Quark Controller (CQC) is precisely such a program (and a whole lot more). It is a network-distributed home automation and home theater control program that also includes media management features and a robust interface designer for making cool user interfaces for touchscreens, PocketPCs, and WinCE devices.

Dean Roddey, who posted a few messages back in this thread, is the software engineer who designed CQC. At my request, he wrote a device driver for CQC specifically to control the 990 via its serial port. I currently control the 990 (and the rest of my theater components) with a touchscreen interface in my theater, but I also control the 990 (and its second zone output) and my whole-house music system using wireless touchsreens in my kitchen and bedroom.

Check out CQC here: CQC

And check out my system here: My Page

HTH,
Ken