Kevin's take on the ball pit project from his blog: A lot of people have asked me "Why would you, as an adult, want to own a ball pit?" And the answer every time is "because of this xkcd comic." There's something about a ball pit that just screams PURE FUN. You can't sit in a ball pit and not smile. It's like you turn to jello and float on plastic bubbles of multi-colored joy. I have spent a large portion of my summer in my balcony ball pit, and I could go on about stress-relieving effects, or about "deciding what 'being an adult' means in the 21st century", or even about how this is probably something you dreamed about as a child/teenager/college student, but really, it's a ball pit on a balcony. How does that NOT sound awesome?
Kevin's how-to post includes very real, accurate instructions - as well as tips on how to "friend-proof" the pit (yes, people just MIGHT be drinking while using the pit, so safety first!) and advice on what to include (such as a small basketball net to give people something to throw the balls at, as Kevin says, other than each other...or you). It also includes a complete list of all the necessary materials, including the essential $2 inflatable shark.
All the info and more pics: How To Build A Ball Pit On Your Balcony
Images: via Kevin James Hunt