09/09/09: What Does It Mean?
Nothing. It's supposed to be a bad day to get married, a decent place to play golf, and a great promotional opportunity ("this Wednesday, September 9th, 2009, as many of you as are available will watch Galaxy Express 999"). But despite the numerological portents to which some cultures attribute it -- "In Japanese, the word for nine is a homophone for the word for suffering, so the number is considered highly unlucky -- second only to four, which sounds like death" -- it's just a damn number. Still, it does provide an excuse to play this delightful clip from the old Square One show. (h/t sethdmichaels.)