Today, 11.11.11 is the last binary day in this century! The next binary day will come at 01.01.00, which I doubt a lot of us will be here to experience!
This is a day for celebration, both because it is a unique day, but also because TES:Skyrim is released!
Side-note: If someone was born on June 11th, 1981, this is their 11.111th day on the earth, how cool isnt that?!