When I built a stone patio outside my house, I built it next to the garage rather than next to the house. I kind of like having it 30 feet away from the house, because it gives us a little privacy for grown-up patio parties, and the noise of our revelry doesn't wake up the kids.
One interesting feature of being next to the garage is that we have a window overlooking the patio. I thought about a window box, curtains, or some other way of dressing up the window. But then I put my geeky hat on, and come up with this: an Arduino-controlled mood mural, located inside the garage and looking out.
The core of the mural would be a series of illuminating panes and LEDs peering out of the window. Their color and animation would depend on a number of factors:
* Wind Speed, as measured by a wind gauge mounted on the roof of the garage.
* Ambient light.
* Nearby noise, so people talking on the patio will trigger a more interesting and lively pattern.
* Time of day.
* Maybe add a wifi element like a Twitter interface so my friends could control it via iPhone.
My garage is unpowered so I'd need a solar panel and lead-acid battery to keep it running at night, when it'd get its most use.