About a year and a half ago, maybe even two years ago at this point, I joined SAGE, the Systems Administration guild part of the Usenix organization. Usenix hosts Unix oriented conferences and other cool computer related events. Part of what SAGE does is publish a series of short booklets, most of which are available as free PDFs to users, and for sale in paper form. Members also get their choice of one of these books free each year of membership. They’re all pretty well done, so I think I’ll probably end up with a couple of these. It’s way easier to read these than their PDF counterparts.