Because they are so small, if you build them into blocks it will make two mini quilts about 18" square, plus sashing. If you use them together then 25" square, plus sashing. I would use them in a border instead to spread the effect out more. If you make a pinwheel border and alternate fabric types, you can get over 300 linear inches of border.
http://quilterscache.com/B/Borders.html