One of my first specialty rulers, a Kaleidoscope, 45 degree ruler, by Marilyn Dohaney. This even came with great instructions, resulting in a quilt with seams pressed oppposite directions and neat intersections. Easy, despite what it looks like. I bought this ruler in 1989, and went wild with it for a time, probably due to the included instructions. I marked the back with masking tape (ugh) to help keep everything in line, and later learned about using painter's tape, a vast improvement. Masking tape left icky residue. 
This is another favorite ruler but I found the lines hard to see, resulting in eye strain and error - hence the bright orange marking product. This product comes several strips to a package, they are reusable, and can be cut. No residue. I found if I licked the back of the product (oh yeah, quilt-y germs and all) it would stay put.
This was my first quilt I made using the Kaleidoscope Ruler - now, there are many similar products, but I still like my first. It is machine quilted using a rainbow type invisible thread, and two of the borders are done in a cable, using blue thread and a walking foot. I was new to this machine quilting stuff back them! The outside border is done with invisible thread, straight line stitching jogging between the white moons.
I purposely left my DH's stocking feet in the photo, as well as the lovely blue spring sky. We quilters should have a special commemorative day for willing "Quilt Holders."
Close up of the lovely crinkles and wrinkles, etc.
If you are new to quilting, be sure you understand the difference between a 45 degree ruler and a 60 degree ruler and a "Peaky and Spike" type set of rulers. Yep, a lot of us (uhhh ... me ...) have forgotten until we make the dreaded mistake!
You know, just pulling this quilt out of the closet, taking photos, etc., and I get all gung ho to make yet another! Arrrghhh - there is no end to what MORE we MUST make!