I see a lot of people using cinder blocks and mixing up cement to sink cover. Why not fill laundry jugs with sand or gravel and join two or more by a short cord or cable. Then the cord could be draped/looped over a tree or pile of brush, or a small drywall screw would hold the container in place on a pallet.
Sand weighs about 15 pounds per gallon, so you could use that to calculate the equivelant weight needed. Since the weight would be divided between two or more containers pulling down on opposite sides, the strain on the handles should not be a problem.
