LOL Sorry to laugh but I hear this ALL the time. It's amazing how many rats lose toes, ears, tail tips etc. You should take him to the vet and have the doc look at it, as there is a chance of infection. Can you try to wrap it at all? If it's hanging it's probably very painful for him and he should be seen by a vet. He will also probably need antibiotics as well. Please take him to the vet! I hope he feels better soon. Poor ratty.