In the past I have done reviews of the textbooks and platform at Flat World Knowledge. In December 2012, Flat World announced a change to their business model which previous to this change always gave a free web version of the book as part of the program. The new announcement was met with mix review but with anything in life, things change. The change, effect Jan 1, 2013, now charges a minimum fee for web content. The beauty of open content is that once you publish it you can’t change the publishing rights. This means that anything published prior to January 1, 2013 still lives within the creative common license to which it was originally penned. The question you maybe asking is “how do I get the free books if they are no longer free?” and that is a great question. The answer is we have Aaron Schmitz to thank as he archived many of the book prior to the change. You can read more about this and access the books here.