Since coming across this method of making a square many years ago I have used it on its own and as a building block for many items.  I call it a yin yang square because it reminds me of the yin yang symbol with the half-way reverse, each different but yet the same – the opposite side of each other, flowing toward and complementing one another. (Quite the mouthful!  Quite the mindful!  But isn't that the point?!)

Shown is the square in that lovely linen yarn I discovered at a church sale and, by Googling the words on the label which I thought were not in English, found the skeins were linen from a shop in Sweden back in the Fifties:  I have ongoing gratitude to whoever had this in his/her stash for half a century.

Here the square is hung up in the kitchen as a hand towel, knotted at two corners and hanging in a nice loop;  this is used for the frequent hand dryings that occur by the kitchen sink and the linen material plus the loose drape of the towel makes it dry quickly.   The amber  towel is for more thorough drying (like after hand- felting in the sink where arms-up-to-elbows tend to get involved) and is a linen/cotton blend; it is also a yin yang square but has a border of seed stitch.  I wonder how I did that?; will have to go and look at it. *

The long purple rectangle is also linen and is a dishcloth as is  the far left cloth also made from linen in the yin yang square. 

A yin yang square is made like this:  Cast on 3 sts. Row 1  Increase one stitch in first stitch; knit to end of row. R 2  Increase one stitch in first stitch; purl to end.   Row 3  Increase one stitch in first stitch,  knit to last stitch, increase one stitch in last stitch.  Row 4  Increase one stitch in first stitch, purl to last stitch, increase one stitch in last stitch.  Repeat these four rows until 45 sts.  Work Row 1 and Row 2.  (47 sts).  Next row begin again with Row 1 as follows:  P2tog, purl across row.  Row 2  K2tog, knit across row.  Row 3  P2tog, purl to last 2 stitches, p2tog.  Row 4  K2tog, knit to last 2 stitches, k2tog.  Continue until 3 sts. remain.  Cast off.

*  I have no idea how I added the seed stitch border (I made the towel, in senior's parlance, "more than twenty minutes ago")  and I am a bit impressed because it looks like it was done in the original, not added later, which means I must have figured out how to start the seed stitch border and then have it nestle nicely into the stockingette.  Hmmmmm; I didn't know I could do that.

Two of the items shown are green.  Happy St. Patrick's Day!