Do games hold the secret to better productivity? If you've ever found yourself engrossed in Angry Birds, Call of Duty, or a plain old crossword puzzle when you should have been doing something more productive, you know how easily games hold our attention. Hardcore gamers have spent the equivalent of 5.93 million years playing World of Warcraft while the world collectively devotes about 5 million hours per day to Angry Birds. A colossal waste of time? Perhaps. But what if we could tap into all the energy, engagement, and brainpower that people are already expending and use it for more creative and valuable pursuits? Harnessing the power of games sounds like a New-Age fantasy, or at least a fad that's only for hip start-ups run by millennials in Silicon Valley. But according to Adam L. Penenberg, the use of smart game design in the workplace and beyond is taking hold in every sector of the economy, and the companies that…