What kind of keychain weapons do you have? Also, I have seen these little metal bar things that some martial arts people use that they have on keychains, does anyone know what this is? It's like a small round piece of metal basically.
Sounds like you are asking about a kubiton. I don't carry anything on my keyring except for keys and a fob.
There are a few options. Pepper spray is available in many key chain models. So are some knives, kubotans as mentioned above, saps.. etc.
