Over at Nate's it was mentioned that many people, when faced with a situation like at VaTech, don't know what to do. They are paralyzed by the fear and the chaos of the situation. This is true, but it need not be true for me or anyone else. What it takes is making a decision.
When I say make a decision, I mean to imagine a circumstance and play out your response to it. There have been numerous shootings at schools, malls, and restaurants. What will you do? Where would you go? Where might you take cover? Are there dividing walls? Back doors? These are quite simple questions and as we all tend to visit the same places over and over the answer to these questions are also quite simple.
If so lunatic with a gun or a knife starts attacking people near you, you need to be able to act with the minimum amount of thought possible. Fear can cause the mind to freeze so don't count on your incredible intelligence when that day comes. It likely won't be available to you. And with the adrenaline coursing through your veins your legs won't be good for very long either, so quick action is critical to the survival of your loved ones and hopefully yourself as well.
I wrote an article previously about being vigilant. It's a good read and well worth two minutes of your time. Being mentally prepared could just save your life.