I've shared these before, which are a curiosity that fell out of some code that I wrote to tile dominos for a puzzle. Rather than thinking of it as packed diamonds, I started from triangles, then paired them, and arrived at the very op-art look quite by accident.

It's not so far away from the "tumbling blocks" quilt pattern, but picking colors for it seemed challenging; three solids is just too flat. Now I am considering the idea of using two greys plus an assortment of prints, lightly sorted.