The Japanese word Sashiko means "little stabs" and the stitching was originally used to reinforce clothing. In contrast to the beautiful Japanese silks, Sashiko is considered a folk textile because it was created and used by the peasant class.
Traditionally it is done with white Egyptian cotton on indigo fabrics. But, as with all things involving stitchers, it has evolved and you can now find Sashiko embroidery using a variety of thread colors and it is mostly for purely decorative purposes.
If you are not a purist, you could use Pearl cotton or embroidery thread, but I love the feel and look of the Egyptian cotton.
There are hundreds of Sashiko designs inspired by nature, and as with modern quilting, the negative space is an important aspect of the overall design. The symmetry of the designs are very soothing and stitching can be very relaxing. Using a Sashiko needle (about 2 inches long) you make a series of equally spaced stabs until you fill the needle, then pull it all the way through without tugging or causing puckers.
I find Sashiko very relaxing and a wonderful addition to my stitching life. My area does not have shops which carry products for Sashiko which means I internet shop. My two favorite places are http://sylvia-pippen.com/
They both carry fabric, thread, needles and kits! There are also many instructional books available which will help you learn the Sashiko stitching technique. I encourage you to try this stitching art form which will add a bit of peace to your life :)