I've been doing some intermittent art-related yak-shaving by way of tinkering with JS libraries for manipulating color and I am digging Stephens Nunnally's 'Iris', which lets you work with hues in red-yellow-blue (subtractive color, like mixing paint IRL vs red-green-blue, which is how pretty much every digital color picker works)
Hacked together with Chart.js it presents interesting possibilities






