Image: My 'yellow' tank.

The incinerating toilet takes care of my black tank needs perfectly, but it's expensive to run, so I rigged up this homemade urinal with a small tube (with a loop in it for a literal 'P-trap') that goes into this old gas tank, with a tee for an air vent (via a charcoal filter, which removes all odor) and a quick release so I can take it out and empty it. Piece of cake!