I've got this thing for quilting my quilts with circles. For my templates, I have a collection of template weight plastic ones which range from those meant for applique to the larger ones I've cut out myself. But a couple of Christmases ago, I gave myself the present of a set of nested acrylic circle templates.
If you've never run into these things, they are wonderful! And if you're not into circles, they also make nested squares, hexagons, diamonds, triangles and more. Check them out!