There is also Free As In Freedom: https://web.archive.org/web/20150103152231/https://static.fsf.org/nosvn/faif-2.0.pdf
Ooooh! And while looking for a legal-in-as-many-countries-as-possible gratis copy for you, I found out that 2.0 exist; instant karma. :)
Anyway, that's the one that gave me and mine a bit more insight into the man behind the software. It was a bit much for my then-8 year old, but some of that was just chronological snobbery on his part and needing a bit more experience with this thing called "life".
It would make a quick, easy, relaxing read for an adult or teen.
