EZ Quilting makes a great variety of rulers to compliment your squares and rectangles. I started by ordering the 'Easy Circle Cut' for Brenda's 'Circle Time' and 'Spin Off' patterns. Check them out at http://www.amongbrendsaquilts.com/ Then came 'Easy Hearts' for those wanting to do fusible applique. Next, someone requested the 'Easy Six' for stack and whack quilt cutting.
Last spring when Tim and I went to 'Quilt Market' in Pittsburgh, I went to a presentation by Darlene Zimmerman. I couldn't resist her line of 1800 reproductions so ordered the fabric and patterns. Then I found out the patterns call for the 'Easy Dresden' (with more possibilities than plates or fans) and the 'Companion Angle'. Of course there is always something that just looks interesting, so along came the 'Tri-Recs' and 'Tall Triangles'.
If you want to see the rulers, tutorials and free patterns, take a few minutes to check out http://www.ezquilts.com/