I took a small piece of 1/2″ MDF and a few screws to make a simple spline jig I needed for an upcoming project.  If you are not already aware a spline jig allows you to make kerf cuts on the corners of project that you can insert thin pieces of wood (splines) to reinforce the joint.  If you use contrasting wood it can add a decorative touch as well.  You can use it on jewelry boxes, keepsake boxes, or in my case a picture frame.  Typically it is used in mitered joints as the end grain glue connection is not very strong.  By adding splines in which the grain of the spline runs perpendicular to the joint, you improve the strength considerably.  You can center the spline or make multiple offset splines to achieve the particular look you want.  Experiment with your options and HAVE FUN!