I read 'Underground' due to my growing interest in early hacking culture, as well as the links to Julian Assange; and I'm extremely glad I did, this is one of the best books I have read for a long time, not just for the detailed descriptions of early hacking & phreaking techniques, but because it is a thrilling and fascinating real life story; thoroughly researched and very well written.
Dreyfus covers a lot of ground detailing; hacking the pre-internet on early Apples & Ataris, amazing phreaking techniques, the BBS scene, a vast array of international characters, stories of Hackers on the lamb avoiding the FBI by seconds, the effects dedicated or rather; obsessive hacking has on personal relationships, arrests, court cases, and much, much more. All this combined with Dreyfus' flowing, easy to follow style made this a gripping read.
One of the things I liked most about this book is that it doesn't just follow one hacker, or one group of hackers; many of the successful international hackers and phreakers at that time are covered in great detail. From their first interest in computing to their greatest hacks, the links between the groups, the personal connections and relationships, as well as (for some) their ultimate fate at the hands of the various 3 letter agencies out to get them. Some of the hackers in this book were among the first to go to court in their respective countries on hacking charges, and the court cases and their outcomes are described in riveting detail.
Personally I think Underground is a must read for anyone interested in 80's/90's hacking and phreaking, or for anyone interested in Julian Assange's early days as a hacker (although real names weren't used; it wasn't hard to figure out one of the featured hackers is him!) But it should also appeal to anyone who enjoys a thrilling, well-written, real life story.