It’s the hundredth anniversary of the publication of the first crossword – check out today’s Google Doodle.
On a related note, crosswords are possible in English (or other natural languages) because a large enough proportion of the possible strings of letters are actual words. I learned this from chapter 18 of Information Theory, Inference, and Learning Algorithms by David Mackay (which you can read online). (Chapter 19 is about why to have sex, from an information-theoretic point of view.) And Dr. Fill is a crossword-solving program by Matthew Ginsberg which did not win the 2012 American Crossword Puzzle Tournament.