National Day Calendar: Celebrations on the daily

National Taco Day, National Talk in an Elevator Day, and National Lima Bean Respect Day are examples of days that aren't quite national holidays, but which provide excuses for fun (and, in the case of some companies, good marketing opportunities). Correspondent Luke Burbank meets the folks behind the National Day Calendar, where every day provides a reason to celebrate something, from the obvious (pizza) to the obscure (scribbling).