It's called The Frog Log. You can see how it works via the accompanying video.
The product is sold on Amazon for around $36 and gives the creatures a way out: An inflatable platform with a mesh skirting and ramp attached that floats in the water courtesy of a weighted pouch that keeps it in place. You attach it to the edge of the pool and, voila.
Still no luck with mice, chipmunks, rabbits....you get the picture.