I've made many, many scrap quilts. In fact I don't remember ever making a quilt for which I had to buy all the fabric. Friends give me all their scraps, and I mean down to the lint. LOL I,ve made a Freedom Quilt (log cabin with anything around a center piece, square or not) several confetti quilts. (Flip and sew onto foundation strips, then sew the strips together.) Scrappy Trails (Jacobs Ladder, but this one had a background of a single color.)
When I first starting cutting up fabric left from clothing sewing, I made 6 inch squares. The stuff that wasn't square got to be 6 by whatever. Last year I went into this box and started sewing these 6 inch strips into squares. I just picked three or four (or more) strips that would total 6 inches/ Size was my measure, not color or pattern. I sewed these squares into rows like a rail fence, put that on the bias with white corner triangles and a piano key border, (more 6 inch strips, any width). I thought of it as a charity quilt. At the quilt show, that was the quilt that the photographer put into the local paper with a friend admiring "a colorful quilt". Scrappy quilts can be quite stunning.