If you've ever seen the wild predictions from 50 years ago about flying cars, jetpacks and the sort, that basically sums up this book. I've long been a fan of Michio Kaku and looked forward to this book, but the overall presentation is so far-fetched that it seems he'll believe just about anything. Again and again very real technological constraints are glossed over. Even the more interesting moral conundrums that come up from things like the ability to peer into someones thoughts are given only superficial treatment. This book was a huge disappointment.