Enough playing around...
I've ordered a couple personal alarm keychain things whose advertisers rate it at "140 decibel". These will serve a dual purpose: some sort of protection when walking to and from work. It's getting dark earlier and I'm not very imposing. It's also a crime to carry pepper spray where I love. D'oh. They will also serve to damaging my hearing. I'll worry about where I'll find a place to use such a loud device later (People would tend to come investigating).
It should be well and truly painful but as the lame saying goes: no pain no gain.