NeeView - Display two images simultaneously
calibre - Ebook manager, viewer & converter
Soda PDF 3D Reader - Read any PDF document like a book using our patent pending 3D technology!
Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
ComiXed - ComiXed seeks to be the ultimate digital comic book management system.
Adobe Digital Editions - ebook reader software