I've been working on turning my PC into a DVR, as suggested here several times. I found a very cool-looking product from D-Link but wanted to find out if it would work with any of the third-party PVR software apps like MythTV or SageTV. I found the thread in the link on the SageTV forums discussing the possibility of getting SageTV to control the D-Link box.
The forum discussion runs to 11 pages over many months. Seems that D-Link based their firmware on Linux but is violating the terms of the GPL by not making the modified derivative code available. This means that the hackers in the SageTV and MythTV communities can't make the D-Link product work the way they want it to.
A member of the Sage community who's a lawyer took up the challenge and for a while it looked like they were going to win and D-Link would release the code. Then D-Link did an about face and stonewalled, and the code is still not released.
About the same time all this was happening, board members found out that a European group known as GPL-Violations.org had sued D-Link and won for the exact same violations in Germany. Seems that D-Link doesn't think the GPL is "legally binding," according to their executives.