Sometimes the simplest jig designs provide the best solutions to woodshop cutting situations. Take this simple shooter board styled squaring jig. While it doesn't include the longer fence and stop positioning capabilities of the bridged crosscut box, it does provide a quick and sure means of squaring the end of your workpiece in preparation for subsequent cutting operations. A similar jig made with the blade tilted to 45 degrees would be a great asset for mitered box making.

Start by adding a Miter Slider to the line of mounting holes closest to the edge of a large Built-It Panel and adjust for a good fit in your table saw's miter slot. Add a T-Slot Panel Connector to the edge nearest the Miter Slider. With the Build-It assembly in your miter slot, measure the distance between the T-Slot Panel Connector and the blade. Flip the assembly upside down and cut a section off the UNUSED edge of the Build-It Panel that is about 1/4" wider than your measurement. Place the Build-It assembly back in your miter slot and attach the cutoff to the T-Slot Panel Connector. Now run the assembly through the saw to trim the jig to the blade. Using (2) #8 x 1" pan head wood screws with washers, attach a fence to the trailing edge of the Build-It Panel. Square the fence to the cut edge nearest the blade before tightening the fasteners. Don't forget the Build-It Clamp for safe and secure cutting.