I adopted Koda from Cat Depot early 2016, and kind of thought I was doing him a favor. It turned out to be the other way around.
One night, Koda woke me up at 2:30 and wouldn't leave me alone. Believe me, I tried to go back to sleep, but the cat was insistent. Eventually, I was awake enough to think he might want something. Of course, I thought something would be along the lines of needing the water bowl filled.
I followed him through the house in the dark, and was surprised when he stopped by a wall. Turns out the AC was leaking water into the wall to the point where it seeped out and made a lake on the floor.
Koda supervised while I turned the AC off and dried up all the water, and once I was done, he went back to his favorite napping spot. Thanks to him I caught the water so early it didn't make any serious damage, and it was a manageable amount. Had I kept sleeping, things would have been much worse.
I always imagined one of my three dogs waking me up if there was a problem. Turns out the cat is the one to trust.