I heard about a new book intriguingly titled Lonely Planets: The Natural Philosophy of Alien Life. The web site describes the book like so:
David Grinspoon‘s new book, Lonely Planets, is a provocative blend of science, history, philosophy and memoir, which uses the question of alien life as a mirror on human awareness, desires and potential.
Sounds interesting. Grinspoon is a planetary scientist. (Like throretical physicist, another cool gig) The web site has lots of cool info and is quite well done (in an artistic sort of way).