Happy Leif Erikson Day! It's a joyous day indeed celebrating the Norse explorer for supposedly being the first European to set foot in North America. The Spongebob episode about the holiday is probably what's given it the most publicity.
Fun fact: October 9th has nothing to do with Leif Erickson himself, but rather marks the day that the ship the Restauration arrived in the New York from Norway, bringing with it an influx of Norwegian immigrants.