I finished a long-overdue t-shirt quilt for a friend made out of her old lacrosse t-shirts.
I used a 12 1/2 inch square ruler with a rotary cutter to cut the t-shirts out and arranged them in a grid. I sewed the squares into rows, then sewed the rows together. The back took a bit of careful piecing, as I was a bit short on fabric. I made a quilt sandwich with the top, back and batting right sides together and just sewed around the perimeter, leaving a gap to turn it inside out. To finish it off, I hand-sewed the gap closed and used embroidery floss to tie the quilt together at each of the corners where the squares met.