I don't have a pattern, per se. I saw a picture of a tumbling blocks quilt and asked a friend to help me set it up. I made strips of alternating parallelograms and triangles and then sewed the strips together so that the matching triangles came together (making the third part of the box). I hope that makes sense (I don't have the quilt here to look at it).
Someone told me that the pattern is called "Not your grandmother's tumbling blocks" if that helps.