This is the kind of book that will appeal to computer nerds, and perhaps no one else, but since I am a computer nerd I quite enjoyed it. It is a true story involving computer hacking, and one of the earliest ones. The protagonist of this story is Clifford Stoll, who was trained as an astronomer but was managing computers at the Lawrence Berkeley National Laboratory. One day he asked to look into a $.75 discrepancy in the billing for the computer accounts. With a magnificent obsession he tears into it, and eventually traces everything to a Soviet spy operating out of West Germany. Along the way Stoll has to deal with various agencies that don't really know what to do about this, and wonder if it as even anything they should worry about. After all, a 75 cent accounting error is not a big deal. But when it is clear that a foreign agent is looking for information about the Strategic Defense Initiative (aka Star Wars), it is time to take action.