A trick I learned recently in the Nocternal House, at the Territory Wildlife Park.
The animals are in glasss cages, in very low light, and flash is not allowed.
I was using an AF 50mm F1.8, turned the ISO up high,,swicthed to manual focus (focus assist light reflects off glass), and a monopod.
Live View allowed me to gain more accurate focus than was possible with the viewfinder.
Here is an example photo of a Northern Quoll taken using this method: