Scribd is a social publishing website which allows users to publish their documents and to share, embed, print, download and add comments. According to the Scribd website it creates an index of all the words used in your work for search engine optimization.
WordPress and many other blogging platforms allow users to create pages and to write a book online. WordPress allows you to keep total control over the content and sharing options are available through Publicize. For more information, go to the WordPress support page.
Lulu allows authors to publish and sell their book online, while promising to ‘make publishing simple’. Lulu provides many services which include editing, book cover design and distribution packages. Lulu allows you to start small with a small distribution package to a total global reach package which spans Amazon, Ingram and BarnesandNoble.com and offline bookstores.