The idea behind Kurzweil and Grossman's Fantastic Voyage is that if you can make it through the next 50 years, you might become immortal. How will that be possible? Through some rather science fictional steps, it turns out, including taking advantage of the latest in biotechnological breakthroughs and not-yet-invented nanotechnology. Is all this longing for immortality driven by an obsession with youth or a fear of death? Readers can judge for themselves, as both Kurzweil and Grossman reveal the personal histories that led them to develop this plan. Fantastic Voyage is written in an easy-to-understand tone, with lots of sidebars giving examples of what the future holds for medicine and health. Whether or not you think that science will find a way to keep our bodies or our disembodied minds alive forever, this book is full of diet and lifestyle tips. For instance, the authors suggest carefully controlling the body's overall pH at an alkaline level, meditating, eating a diet composed mostly of vegetables and protein, and taking loads of supplements (Kurzweil downs about 250 pills each day). The dietary options presented here will mostly only be practical for people whose income levels can support buying organic produce, fresh fish and meat, and top-shelf supplements. The authors cavalierly state that we are living in a "time of abundance," but it seems likely that most who are able to follow this regimen will be Americans of a fairly high socioeconomic class. --Therese Littleton