Nate just sent me Lev’s latest book Software Takes Command which you can downoad as pdf or doc. It is licensed under CC and the book takes on some of the characteristics of software (from the opening page):
One of the advantages of online distribution which I can control is that I don’t have to permanently fix the book’s contents. Like contemporary software and web services, the book can change as often as I like, with new “features” and “big fixes” added periodically. I plan to take advantage of these possibilities. From time to time, I will be adding new material and making changes and corrections to the text.
So, like an rss feed I will need to go back for updates.