Besides eating harmful insects and pollinating plants, bat poop or guano is actually a very beneficial fertilizer. It is so strong that people who collect it have to wear gas masks and protective clothing. Farmers benefit greatly as guano is the best fertilizer.
People also are finding that Vampire bats contain a blood thinning chemical that can help stroke victims and others that need it. Also their ability to use echolocation is very interesting as we research to learn how it works and how it may benefit humans.