I recently 'invented' a nested bowl using a large, deep rectangular
leftover dish (lasagne sized) and a smaller, square dish that would sit
inside the larger with rolled tea-towels acting as a bumper all around
the inside of the larger dish.  I have 2 large kinetic mutts and in two
5 hour stints this last weekend, it was only stepped in once but nothing
hit the carpet other than a wet footprint.

Sat it right behind me (driving) on the floor in front of the sink
cupboard. Worked like a charm and held enough for the dogs between
rest-stops.

Eric
"Keep your stick on the ice, eh?"
80 Vanagon 'Rusty'