The Saturday sky idea got me thinking. Here's our sky - we've had a lovely heat wave going for over a week now.
A vertical section of it, pixelated with the photoeditor:
A (somewhat simple and hasty) FairIsle pattern using colors sampled from the pixelated photo:
I find this to be very useful in helping me to truly "see" the colors which make up a natural object or phenomenon. Just look at the multitude of hues present in a basic "blue" sky.