Black Friday, the biggest shopping day of the year, isn't something to take lightly. Considering the crowds that will be lining up in just three days, it’s highly advised to start practicing your defensive moves now. And, you might want to be armed with more than just a super-charged coffee. Last year, a woman pepper-sprayed fellow shoppers to get her hands on a discounted Xbox 360 – and that was one of the minor incidences.   Or, you can just skip...