iTunes Remote
Seems to me that Apple is on the right track with the Airport Express. Being able to play music from my computer to my home stereo is the way to go. However, I hate going into the study to change songs. Why not a remote that has the interface of my iPod, connected wirelessly (via AEX) to iTunes? The actual music would stream from my mac to AEX to the amp, but the control would be through the remote. To make it truly useful, it would also need IR to control the amp volume, and all the other components.