If you want your tablesaw to serve double-duty as a router table, check out this space-saving version first. It solves the problems of a too-short rip fence, dust collection, and eventual sagging that plague most such tables. This table has a simple but effective fence that is tall enough for vertical routing and has a replaceable insert. The fence clamps to the tablesaw's rip fence, so adjustments are easy and it's simple to put on and take off. Above-the-table dust collection is integrated into the fence, and a rigid plywood frame keeps the table from sagging.

From Fine Woodworking #216