A drinking glass holds water, but only if you hold it the right way. Tip it too much one way or another and you lose control of it as it spills onto the floor. A bucket also holds water in much the same way, but if I take it by the handle and swing it with enough velocity, the centrifugal force created will hold the water in place. I know that a sponge can hold water too, at least until I squeeze it. Same goes for paper towels. If I put water in a bottle and screw the lid on tightly I can...