Calibre Web - Calibre Web is a web app providing a clean interface for browsing, reading and downloading eBooks...
calibre - Ebook manager, viewer & converter
Komga - Media server for comics/mangas/BDs with API and OPDS support.
FBReader - FBReader is an e-book reader for various platforms. Features:
Ubooquity - Ubooquity is a free, lightweight and easy-to-use home server for your comics and ebooks.
Google Play Books - Google Play Books lets you search, preview, and buy millions of books using Google Book Search.