Well, the humanity just made another step toward the future as it was predicted by Michio Kaku. Like he said "[chips] will cost about a penny, the cost of scrap paper. Computers as we now know them will disappear; they will be everywhere and nowhere, ubiquitous yet hidden, just like electricity and running water". Now we have computer that costs $5 and pretty decent to that. And its not only just theoretical step which doesn't have much practical applications like most of the innovations when they are presented for first time, but its actually something that a lot of us need for different reasons. And its certain that the number of these reasons and applications will keep increasing steady over the next years. For myself I'll need few of these for my hobby 3d printing projects. If one can't find reason to own Raspberry Pi Zero, think about it like $5 investment to promote trend and bring a little bit faster the future to us.
If by any chance somebody hasn't read yet Michio Kaku's "Physics of the future", I wholeheartedly recommend to do it.
Physics of the Future