I always carry my keys in my hands when I walk to my car, with the pointy part sticking out. I can't imagine it would feel too good lodged in some jerk's eye.
According to the Jane Doe Foundation which is shilling for Deval Patrick, these ads are based on an irrational fear of strangers and are unfounded. They stress that most rapes are committed by relatives. Like, Deval Patrick's brother-in-law who didn't sign on to the state's Sex Offender Registry. But you can't say that either because that's a private family matter. Is there no Principal that the Libs wpn't sell out on?
Ah yes, field-expedient weaponry.
You're right, that would ruin a thug's day, alright...
You have a good attitude, and field-expedient weapons are better than no weapons at all ... but there are plenty of quick-opening utility knives that would be even better. Guns, of course, are generally better than knives ... if they're available.