A friend of mine has 2 cats and one of those water systems where the big multi-gallon bottles are inverted onto a dispenser. The cats have figured out how to press the lever which opens the tap. My friend says she hears her guys chasing each other up and down the hall in the middle of the night, then they make a pit stop in the kitchen and she hears "glug, glug,glug" while they tank up before another run. Fun and games!!!!