Mojang’s popular game Minecraft has sold over 54 million copies. But that, and the $2.5 billion that Microsoft just paid to acquire the company, dramatically understates the impact that this game has had on my third grader and his friends. They all wear Minecraft gear and watch Minecraft videos on YouTube. And several of them completed a week of Minecraft Camp over the summer. The way I see it, $2.5 billion just became the most anyone has ever spent on a babysitter.

+ The Verge: Why parents are raising their kids on Minecraft.

+ Markus Persson, the founder of Mojang (known as Notch), explains why he’s selling — and leaving — the company: “It’s not about the money. It’s about my sanity.”