One of my friends used those little pieces to created a strip of fabric about 18 inches wide. When she has a goodly amount, then she cuts her blocks from the created fabric. she calls quilts made with this fabric "Under the table" since that is where she tosses her scraps. She has a huge table in her studio. I assume there are some boxes collecting the fabric! :)
She is not putting them on a foundation--just sewing pieces together until she gets aprox the width she wants. She had two quilts in our quilt show.
She used solid fabric with her scrappy fabric.