Book: The Cuckoo's Egg
In 1986, a sysadmin at Berkeley finds a $0.75 discrepancy in the accounting software, discovers a hacker in the system and unravels a whole network of compromised PCs. He spends the next 2 years hunting down the intruder with the help (and sometimes the opposite) of a few three-letter-agencies.
This is a great first-person account of a cat-and-mouse chase. Stoll gets a whiff of a hacker using an old account on the system, but rather than shut him down he sets up a wire-tap. In 1986 that meant a PC wired in-line with the phone line which printed every single character coming through. The result was a paper record of what was being typed in real time.
There’s something for everyone here. It’s more than just a book for network engineers - Stoll writes clearly and knows how to build suspense so that anyone might get wrapped up in the tale, yet he goes into enough detail for it all to make sense.
For the Unix nerds out there it also acts as an interesting time piece, giving us a glimpse of what systems were like back then, without the lens of nostalgia. It’s particularly intriguing to read about early forms of password cracking - this was around about the time dictionary attacks were coming into use.
Fans of any non-fiction will appreciate The Cuckoo’s Egg in spite of its age (30 years is a long time in this field…). If you’re still not sold, I’ll boil down the message for you - don’t use the same password everywhere!