To quote myself: "For those of you not accessing this column using shortcut keys, touch screens, or voice-recognition interfaces, reading [this edition of] Geek Trivia is possible thanks to a critical computer peripheral that went on sale  years ago. On April 27, 1981, the first commercial computer mouse debuted as an included component of the Xerox Star 8010 personal computer. So, in many respects, April 27 is the 'birthday' of the computer mouse."
Just another of the many technical debts we owe the Xerox PARC outfit and their vastly unappreciated-at-the-time Alto proto-PC. Happy Mouse Day, everybody. (And yes, this was largely a shameless excuse for plugging one of my old columns. Go me.)