I generally use this day as an excuse to show off my vast knowledge of Mexican history to at least one poor person who says "Happy Cinqo de Mayo" to me. It's not really that vast, but I did take a Modern Latin American History class once and the internet is never too far away, so I'm a pretty realistic fake expert. Well, and since most people know essentially nothing other than "The Mexicans are going to take all those good American jobs that...well, yeah, we don't want those crap jobs, but...stupid Mexicans...also, I love enchiladas", I'm pretty safe.
I was debating writing out a brief rundown of the wars for Mexican independence here (hint: The Battle of Puebla, the reason for Cinqo de Mayo, is not actually that important), but I've decided that's actually kind of silly, since like every news source will also have something written about it today (and every Cinqo de May for years to come) and anybody who cares already knows.
Nothing like holding onto information that really serves no purpose other than to give me a smug "I know something you don't know" feeling. Of course, thinking I'm smarter than everybody else is a key part of my personality...but let's not talk about that.
Cinqo de Mayo's greatest contribution to my life: Company provides Mexican food for lunch today. Whoohoo!