Okular - Okular is a universal document viewer based developed by KDE.
calibre - Ebook manager, viewer & converter
Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
Adobe Digital Editions - ebook reader software
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
Calibre Web - Calibre Web is a web app providing a clean interface for browsing, reading and downloading eBooks...