Hexagonal Cross Stitch
As an example, Susan showed a picture of Mary Shephard’s piece “Wallpapers in Cross-Stitch”:
If you are familiar with repeating two-dimensional patterns, you will know that there are precisely 17 distinct pattern types, known as wallpaper groups. I adapted a small piece of pixel art I had created a couple of years ago for a laptop sticker, leading to my first ever cross-stitch project:
I made a bunch of mistakes in transcribing the pattern, and you should see the horrific mess in back. I’m quite happy with the finished result:
There are five large hexagonal cells, containing the five symmetry groups that are not possible using traditional cross-stitch: reading in rows from the top, p31m, p3m1, p3, p6, and p6m.
Source: isohedral.ca