Carolyn Mitchell created this free design that uses two sizes of overdyed pearl cotton, a bit of metallic, and some small crystals to make a delightful geometric design.
She used two colors of Colour Complements pearl. You can read about her choices and get a link to the PDF for the free pattern in their post.
It would be easy to customize with different kinds of embellishments and different colors and threads.
I think I’m going to use this to use up many of my scraps of thread!