This is a video from the 30th Chaos Communication Congress on how delroth and shuffle2 were able to reverse engineer the Wii U GamePad. At the end of the presentation there is a demo showing The Legend Of Zelda Wind Waker (GC) running on Dolphin on a computer but being played by the GamePad and being controlled by it as well. This is showing the fact that you stream video/audio to the GamePad from he computer and send input data from the GamePad to the computer. If they can fix some of the video and crashing bugs this will be awesome.
The code for this is currently available on You must login or register to view this content.. It is currently only supported on Linux but is being worked on to work for Windows and Mac.