I wrote an Android app that allows me to tell a UPnP MediaRenderer (like a WD TV Live +, although that particular unit has many shortcomings) to play a movie file that lives on my phone. This sort of functionality is already available in a couple of off-the-shelf androids and will probably be a standard feature by the end of 2011.

I'm told the big advantage of the Apple version of UPnP is authentication, which is not mentioned in the UPnP specs I have read.

I have a MythTV, and ever since that debacle with commercial builders flouting the terms of service at Zap2it Labs I have been paying Schedules Direct for my channel guide.

The lesson from Schedules Direct is that plenty of people who use Open Source are willing to pay for a service that has value.