I have played around with Google books for some time. I like the concept to convert paper to digital, but I figured the books were a sample and not the entire book. Well that is not the case for some books (copyright limited). It is a great source of many books from the classics to technology. I am right now reading Beginning XSLT 2.0: From Novice to professional. I Ordered the book from www.half.com. Who can afford new books? The book when new is $49, and I paid $22. The downside of buying books online is the book is usally shipped by media mail (very slow snail mail), so it may take weeks. I opened up the book on google and finished reading chapters 1, 2, and 3. I do not know how much of the content is available online the book is 700 pages long. But, I figure that I can get a head start until the paper version arrives.