The concept of Leap Day being the only day a woman can propose to a man is an old one and really does have Celtic roots. Perhaps Irish men, notoriously slow at proposing today, were just as reticent to marry back in the old days. Both Sadie Hawkins Day (made popular by the comic strip and later musical, "L'il Abner") and the film "The Gnome-Mobile" are based on this tradition. The latter is often believed to be an Irish film yet it is set in America and the wee folk are not called Leprechauns but gnomes. Still, in this film, the whole Leap Day thing is just a device to get our young Irish-American gal back to the old country so she can get in touch with her heritage and herself.