Having recently acquired (through work) an iPad, I've downloaded a lot of free or inexpensive e-books, and made some attempt at reading a few of them on the system. It's not quite like a physical book, but it's not a bad experience. There have been some formatting or editing issues (presumably because the originals were scanned and turned into text via OCR) - but sometimes you see copy-editing errors in a physical book as well. It means it's slightly less ideal than the "real thing", but I don't think I've running into anything that prevents communication of the author's intent.
Among the books are many that I've long had some desire to read, but never got around to looking up in a store or library - it's easier (or perhaps just implies less commitment) to download them than to go out searching. One of these was the original 1935 book by economist John Maynard Keynes, "The General Theory of Employment, Interest and Money", which led to the so-called Keynesian philosophy in US monetary and economic policy in the mid 20th century. Keynes wrote in the context of the Great Depression, which the world was experiencing at that time, and while much of what he says can be hard to understand, it surely has some relevance to the modern "Great Recession" the world has been going through for the last few years. Below I'll quote some parts of the text I found particularly enlightening, without a lot of comment from me on the matter since to say anything knowledgeable on this would require more familiarity with other economic schools of thought than I possess.