Permutation City: People can run simulations of themselves or entirely migrate their consciousness into computer programs, but existence is often limited to the amount of computation that you can afford, leading to slow existences that stretch time into fractions of realtime. That premise had me hooked, but the book has fantastic thought provoking plot points throughout. Highly recommended.
Blindsight: Amazing first alien encounter book that should be read by everyone that is a fan of the genre. Memorable cast of characters...the Vampires are really interesting. All kinds of introductory scientific concepts throughout. Entertaining and educational.
This is a tangent, but Peter Watts's brilliant novel Blindsight deals with this issue (among many others). Describing how would unfortunately ruin a key plot point.
He uploaded the whole novel to his website: http://www.rifters.com/real/Blindsight.htm but in my view it's more than worth getting in paper: http://www.amazon.com/Blindsight-Peter-Watts/dp/0765319640 .
The book is CC-NC-SA licensed and available for free online: http://www.rifters.com/real/Blindsight.htm
It's also published in real paperback form: http://www.amazon.com/Blindsight-Peter-Watts/dp/0765319640/
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