Instrument panel junction box...
Needed a place to mount the misc bits and pieces for the cockpit bulkhead instrument panel. In addition, I needed to cover up the 5" hole where the non-repairable bulkhead compass used to live. A 6" watertight junction box from the big box store serves quite well.
Terminal block for inst power and ground. DB9 breakout board to connect the GPS nmea stream to a serial to usb cable for the nav computer. Also a handy spot to mount an aux DC power outlet.
Twisted power pairs were home made using 12 wire chucked up in a drill running at low speed. Again, the leads have an extra 5' loop to allow the DC panel to be removed and serviced without disconnecting wires or standing on my head.