A PDF is a suitable file format for creating and reading e-books. However, if you want to open an e-book in most e-readers, like the Amazon Kindle and B&N Nook, you must first convert it to an EPUB.

Free web-based converter PDF-to-Word turns static PDF files into edit-friendly Word documents with surprising, reliable accuracy. It's in closed beta right now, but Lifehacker readers can get in early ...