When It Rains It Pours

To recapitulate: I've got on my needles three summer items - a cotton cardigan, a linen blouse and a cotton-viscose black dress, of which I do mean to finish the first two some (sunny) day.
I'm also deep into my winter knitting - a cardigan, a hat for my son and leg warmers and gloves for me.
So I really don't know what came into me yesterday, but I started a ... thing out of my cotton-acrylic yarn stash. It's a patchwork entrelac ... thing, which might become a blanket or a throw, or just a cushion, I'm not sure yet :)

But now I get it why quilts and patchwork items as a whole are so popular with crafters - creating this WIP square by square is totally addictive!
Here's the pattern if anyone is curious or likes it. I'm sure there is actually a written pattern somewhere, but I came up with my own, as I prefer purling to knitting and I wanted my garter stitch to be made only of purls (as opposed to only knits):

Cast on 35 stitches using backwards loop method and color 1.
Row 1 (RS): purl
Row 2 (WS): Change to color 2. Purl 16 sts, purl 3 tog, purl 16 sts
Row 3: purl
Row 4: Change to color 1. Purl 15 sts, purl 3 tog, purl 15 sts
Row 5: purl
Continue this way, purling 2 rows with each color and decreasing 2 stitches at the center until you've reduced the stitches to 3 stitches of color 1.
Row 33 (RS): purl 3 tog

I'm knitting on 3 mm needles and my squares are exactly 8 x 8 cm. I've got 550 g of different colors and the 9 square piece weighs 30 g. I'm still not sure whether to proceed as until now - without planning, adding each new square on a whim, or to make an effort to design the thing. We'll see ...