
Sumatra PDF
Sumatra PDF is a slim, free, open-source PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows. Why another PDF reader?
Sumatra has a minimalistic design. Simplicity has a higher priority than a lot of features.
Its small and starts up very fast. Its designed for portable use: its just one file with no external dependencies so you can easily run it from external USB drive.