I'm a Southpaw and I didn't receive any cards! I guess there isn't a lot of support for the holiday. Less than 10% of the population is left handed and most of us were unaware we had a special day to celebrate.
Being a "Lefty" has a few pro's & a few cons but overall I think we are just another quirky minority. But, people still like to postulate all sorts of theories, everything from whether left handers have a higher rate of car crashes (I'll say no) to whether we have higher IQ's (I'll say YES!).
There are some impressive lefties in history, including: Benjamin Franklin, Michaelangelo, Leonardo DaVinci, Babe Ruth and even Beatle Paul McCartney. And a few less than impressive ones like Jack the Ripper and the Boston Strangler.
Most people don't realize that our world favors Right Handedness. Handwriting is a classic example where I find 3 ring binders a big annoyance as well as the constant smudge of my left hand smearing fresh ink as I write. I'm not ambidextrous but you do figure out how to function in a world with a "right" bias. For example: I found it was easier to learn to cut with regular scissors than to try to find decent left handed pairs!
By definition, "RIGHT" can mean virtuous, correct, fitting, and suitable whereas "LEFT" might imply evil, ominous, sinister. People even have superstitions like getting out of bed with the left foot means that you'll have a bad day and be bad tempered! But I get out of bed with my left foot EVERY DAY and have way more good days than bad. But who knows? Maybe I have Temper Tantrums (I'll never tell!).
Here is some interesting trivia: It turns out that women's clothes button opposite from mens because long ago women were dressed by servants who were mostly right handed and they faced the woman so.....well, you get the idea. Since men apparently had to dress themselves their buttons favor righties.
Well, Happy (belated/yesterday) Left Handed Day to Southpaws Everywhere!