Not that it totally fits with this thread, but it's a great tool for self defense... STACKING!
I went to an 8 hour class a couple weekends ago and one of the tactics introduced to us was called stacking. In the event you're beset with more than one bad guy it can be a great way to reduce their advantage and give you the edge.
Basically it involves moving away and in a circular direction so that if they're on either side of you, it puts both bad guys more "in line" with whatever you have to protect yourself. It doesn't work in every situation, but it can greatly increase your chances of surviving.
For instance, if there are two bad guys at your 10 and 2 position, you move quickly while giving commands to stay away (or whatever is appropriate at the time) and you move back and either to the left or right to put them both more in front of you. Given the 10 and 2 clock example where you're at the middle of the clock, it'd be like moving from the center of the clock to outside the clock around 3:30 or so. It essentially stacks the bad guys more in line. Of course, they probably aren't going to stand still so it needs to be "on the fly", but it does give you time to Observe, Orient, Decide and Act depending on their intentions. Hopefully going to the next class where they incorporate this into a full force on force class with airsoft guns (not a big fan of airsoft, but this may convert me as being able to actually practice drawing and firing on people with real guns isn't very fun for the role players hehe). Seems like it'd be something to practice and put in your tool box. We did it without even using blue guns. Just the act of moving to put them more in line. Try it (without guns of course), it's simple and effective.