Altered Carbon

by Richard K. Morgan

A 25th century thriller, set in a world where people can easily upload and download their consciousness into new bodies or "sleeves", but where (contrary to David Brin) there's a very strong convention that you should only have one body at a time. Zesty, full-throated and hardboiled, the story keeps moving even though the whodunnit is not particularly strong. The world building is wonderful, with a terrific background of Martian archaeology, holidays like Translation Day (when we learned at last how to talk to whales, after which "as rare as whale meat" became proverbial), and a richly-imagined history that leaves eons of proverbial wisdom washed up in the streets of Bay City California, along with an artificially-intelligent hotel that longs to have guests but at which, because it is artificially intelligent, no one will stay.