The string bag from here worked out as I was hoping and I expect to make more using those dimensions and that design; a simple rectangle with gathers at both ends and along the sides is so – simple! And you can use favourite stitches.
Here it is with knitting projects in it; the size is perfect for hanging on a wrist or a post or chair back and working from it.
It also expands and now has a coat and hat along with the knitting and is still comfortable to carry.
And if it fits in a tea cup it will fit in a pocket or a purse.