There are many quilt patterns made from equilateral triangles. A good source for looking at patterns is
www.quilterscache. One that comes to mind is Thousands of Pyramids. There are a lot of examples on this board under OBW or One Block Wondrs that are equilateral triangles. There are acrylic 60º rulers that you can buy to use with your roary cutter to do perfect triangles. The one thing to be careful of is sewing the bias edges as they can stretch. Starch your fabric well before cutting and sew carefully.