What's the craziest bar fight you've ever witnessed, and did it end up changing how you feel about going out for a drink?

What makes someone prone to starting fights in bars, and how can such situations be diffused before they escalate?
Do you admire the strength that religious Jews, as mentioned by Ari Frenkel, have in representing themselves in an environment that's so hostile towards them?
Have you ever heard of a troublemaker finally meeting their match in a bar? What usually happens to them?