Funny you should mention the key fobs...

The ex's extra key fob disappeared after her daughter had used the car. Daughter swore she had left the keys in a pre-arranged spot near the fish pond.

A couple months later I was cleaning the fish pond and found the keys in the crud at the bottom. The cleaning was necessary because of some other activities of my 3yo niece. Seems she was prone to tossing things in the pond to see the fish move. Kids!!!

Anyway, took it apart, rinsed it in an alcohol bath and dried it with my heat gun. Put a new battery in and I worked great.

Cell phone, once wet, forget it. No hope of recovery....