It's not news that the offices of big, multimillion-dollar tech companies like Google and Facebook have fueled the fervor across industries for open plan offices with ball pits, slides, and other childlike accoutrements. Though these elements are meant to encourage a sense of playfulness and, we'd guess, foster creativity, some have argued that this kind of big-kid decor is, well, infantilizing. In New York, the professional social media network LinkedIn's HQ (in the Empire State Building, no less, a symbol of commerce and industry in the city and state) has a speakeasy. In London, a creative design and branding agency filled an open space in their office with a temporary ball pit to encourage a little fun. And at Facebook's NYC offices, designed by Frank Gehry, you can play table tennis.