Zendo Deb found someone accidentally letting the truth leak into reporting: For self defense, nothing beats a gun.
This is a college town, and every Fall we get inundated with the usual foot-stomping, lemon-juice-squirting, key-scratching, kiai-shouting advice that's supposed to equalize a 97-pound sorority sister with a 260-lb serial rapist.
Every day at work I see someone come in looking for pepper spray or "stun guns" because they're afraid of an attacker, but they don't want to actually hurt them.
All this stuff has a place as a defense if you are surprised or can't get to a sidearm, and some of it is useful as a point on a continuum of force, but ultimately it all requires getting into touching distance of your attacker, who is then, by definition, within touching distance of you. Listen to the advice of the guy in the article with the five black belts: Nothing beats a gun for self defense.
Unless, like the students mentioned above, you spend your days and nights in an area where you're forced by law to resort to yelling, car keys, and lemon juice; in that case, look into pepper spray and a good pair of Nikes...