Expect workplace productivity to plunge today as everyone who ends up on the Google homepage — basically, everyone — starts playing with a digital Rubiks Cube. Its todays Google Doodle, in honor of the 40th anniversary of the frustrating puzzle. (Or try it here if youre reading this on any day other than May 19, 2014.) Alas, the virtual puzzle isnt easier than the real one, at least not during brief attempts to solve it that in no way interfered with work and were conducted entirely as research for this report. Last month, USA Today spoke to Enio Rubik, inventor