Attractive and unique picture frames can be made with basic tools, for some only a saw and a square are needed. It is much easier to cut mitered corners with a miter box or trimmer, if the fit is not exact the angles can be fine tuned by sanding them. Often a cause of poor fitting joints is that the two opposite side pieces are not exactly the same length. A disk sander is a very handy tool to have to adjust the angles to fit, there are plans to build one here.
More at Sawdustmaking.com