In gaming circles, however, Day of the Ninja is as popular (if not moreso) than Talk Like a Pirate Day. That's due in some portion to ninjas making more compelling video game characters than pirates, but mostly because Day of the Ninja was created to help promote a cult classic tabletop game -- a secret origin that even most gamers don't realize.
What cult hit game was the inspiration for the alt-holiday Day of the Ninja?
The game in question is none other than Steve Jackson's Ninja Burger, a comedic quasi-roleplaying game wherein players act as as employees of a fast food chain owned and operated entirely by ninjas. The primary value proposition of the Ninja Burger chain is that it can and will deliver anywhere in 30 minutes or less, no matter how obscure or inaccessible. Each turn, players must use a variety of ninja skills to deliver takeout burgers to such locations as Area 51, the green room of an anime convention (where ninjas are accosted as movie stars), or a mid-race Formula One car. Success or failure results in a gain or loss of player honor, which propels the player towards either a promotion to manager of the Ninja Burger franchise...or seppuku.
Dec. 5 was chosen as the date for Day of the Ninja in 2003 as that was the US premiere day of the Tom Cruise film The Last Samurai, which featured ninjas as secondary antagonists. The Ninja Burger connection was quickly lost amidst the hype of the film and the growing pirates-vs-ninjas Internet meme. By the time Day of the Ninja received serious press coverage on NPR's Morning Edition in 2007, the Ninja Burger origin was nowhere to be found.
That's not just a stealthy seasonal slight, it's a katana-clashing cut of the Truly Trivial.