Calibre Web - Calibre Web is a web app providing a clean interface for browsing, reading and downloading eBooks...
Komga - Media server for comics/mangas/BDs with API and OPDS support.
calibre - Ebook manager, viewer & converter
Ubooquity - Ubooquity is a free, lightweight and easy-to-use home server for your comics and ebooks.
Mylar - Mylar is an automated Comic Book library manager. It automates downloads to series you subscribe to.
ComiXed - ComiXed seeks to be the ultimate digital comic book management system.