My main system:
Apple TV 2 (on top of the Directv Box)
Mac Mini (this is in my office that shares a common wall with the living room. Therefore, I have one HDMI out feeding this setup and another feeding a monitor in my office)
Denon 4311CI - This has airplay built in, so I can control it with my iPad or iPhone.
Eye TV - Hooked up to Directv and the Mac
My living room headphone setup:
Airport Express - This feeds audio to the PS Audio Dac on the shelf.
iPad - I use this for Airplay. I am thinking about adding a 15 inch MBP and setting this area up as a workstation.
Bedside table:
Headphone setup with Airport Express controlled by iPhone/iPad or Touch.
Bedroom TV setup
I also feed this setup the signal from the headphone setup above (via the DAC). Additionally, I have an AppleTV2 hooked directly to the Denon receiver.
The Kitchen:
I use a first Gen iPod Touch with a Pure i20 dock. It has 24/192 DACs built in, or you can send a digital signal to a separate DAC. It feeds a couple pair of small speakers. Since it is limited by old firmware, I use Plex as the main way to stream content to it. I also use it for iheartradio, MOG, and Pandora.
Finally, the hub is is my home office:
The Apple TV on the top monitor is being fed via HDMI from my main system. Since the rooms share a common wall and closet, I have cable going to and from both setups. (The Denon 4311CI has two HDMI outs)
The mini is used for most of my media and the iMac is used as my main computer. Notice an older Denon AVR3300 in this room as well. It was my first Denon receiver and I have been fairly loyal since.