Another one I just discovered is coconut oil. I was enamored of it already for soft skin, cooking and oil pulling, but then I tried it on my underarms, just on a whim.
OMG! It worked! It works as well as the store-bought deodorants! I am so pleased I have one less conventional toiletry to buy. I read somewhere that it had antibacterial and antifungal properties, which is what gave me the idea. It is amazing stuff.