This is gaming table corner and join pieces to use with 2x4s for the edges and a ¼" plywood for the base.  It is designed for a neoprene mat to fit in under the edges to make a nice simple gaming table that can go on top of any table while still being easy to put away.  I used a sliding dovetail for the board joins and to join the corners onto the 2x4s.

Screw the dovetails onto the ends of the 2x4s and then slide the corners on.  Slide the plywood in and then join the 2x4s on each side across the bottom under the edge of the plywood, screw the plywood down onto the stabilization piece and then screw the board joins onto each end of the 2x4s.  Then you can slide the two pieces down on top of each other and have a nice continuous board surface of whatever size you want that can be unhooked and put away.