Saw a reference that reminded me of another couple of great books I read recently (in deadtree form.)
Endless Forms Most Beautiful is available as an ebook (at least on the Kindle)
http://www.amazon.com/Endless-Forms-...dp/0393327795/
But The Making of the Fittest doesn't seem to be
http://www.amazon.com/Making-Fittest...dp/0393330516/