Okular - Okular is a universal document viewer based developed by KDE.
Communifire - Enterprise Social Collaboration Software
Sumatra PDF - Sumatra PDF is a slim PDF/DjVu/EPUB/XPS/CHM/CBR/CBZ/MOBI viewer for Windows.
Bonzai Intranet - Bonzai is an intranet platform with flexible pre-built features for SharePoint and Office 365.
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
hub - The Hub is a versatile intranet portal and collaboration solution that boosts employee engagement and productivity in a digital workplace.