This pattern is called the Fat Quarter bag and I just taught how to make it at my local quilt guild. The pattern is found in M'liss Rae Hawley's book "Fat Quarter Quilts". It is fun and sews up quickly.
To demonstrate for the guild I made several in various stages of completion. The one in black and white fabrics has 6 fat quarters. The colorful hobo one is made from a quilt top, badly made with mixed fabric types from the early 70's. I have recycled it into this bag. It is so homely that I couldn't even give away the leftover three panels from the quilt top.
The bag is huge on purpose. It has elastic and gathered handles at the top edge. It is intended to hold your quilts when you take them to "show and tell" at the guild. You think you will never need bags this huge, but once you have them they are so versatile and handy!