Expletives and MIDI music rose from office cubicles this past Friday: Pac-Man had returned. On May 21, Google replaced its usual blue, yellow, red, and green title with what the company calls a “doodle.” But unlike previous replacements, which have celebrated everything from Pi day to Norman Rockwell’s birthday, for Pac-Man’s special day (the 30th Anniversary of the game’s Japan release) Google pulled out the big guns, er, ghost-eaters. This time, the doodle was an animated and playable version of the 1980s Namco video game, complete with our pie-shaped hero and his multicolored ghost foes: Blinky (red), Pinky (pink), Inky (cyan), and Clyde (orange). But some kill-joys complain that Friday’s Pac-Man play hindered productivity, and set out to determine just how much money had been frittered away as employees avoided their work. The BBC reports that the firm Rescue Time tracked 11,ooo users’ online activity and noticed that Pac-Man kept them on Google’s site about 36 seconds longer than usual. Multiplying those 36 seconds by Google’s 504 million users, that means over 500 years worth of work time spent playing. The firm estimates an average worker’s salary at $25 an hour for a grand total of about $120 million in lost productivity. How Rescue Time …