I assume you know about them already, but if not Charles Stross has a few of his books (including the wonderful Accelerando) as free, freely-distributable ebooks on his site ( http://www.antipope.org/charlie/blog-static/fiction/online-fiction-by-charles-stro.html )
I don't know if you've read Harry Potter And The Methods Of Rationality, but an ebook version of that (up to where it's got to) is available and truly stunning - far better than the actual Rowling books. http://ikeran.org/rationality.epub http://ikeran.org/rationality.mobi