A bit OT, but a fun exercise: every time you see the word "millennium", count how many "n"s there are. The answer is "one" an astonishing amount of the time, even in professionally edited copy. In fact, as of this writing the Google search for "Millennium Falcon" brings up an Amazon ad for—you guessed it—a "Lego Millenium [sic] Falcon". (Full confession: Around 2000, I was mortified to discover that I, a card-carrying spelling Nazi, had been misspelling it for years.)

N.B. You can remember the right spelling by recalling that a millennium is a thousand (mille) years (anni).