Open Source Software for Windows
Thunderbird
A free an open-source email client developed openly by the Mozilla Foundation and the community. Thunderbird is easy to setup and customize and supports POP and IMAP. The email client comes with all features needed to search, filter, write and manage emails, but also have builtin support for live chat between contact and RSS/Atom feed reader.
LibreOffice Calc
LibreOffice Calc is a free and open-source spreadsheet tool part of the LibreOffice software package. With LibreOffice Calc users can manage spreadshets with its native Open Document Format (.ods), CSV (.csv) and other common formats like the Microsoft Excel format. The software is openly developed by The Document Foundation and the open source community while being released under a combination of license including MPLv2.0 and a secondary license GPL, LGPLv3+ or Apache License 2.0.
MremoteNG
mRemoteNG is an open source, tabbed, multi-protocol, remote connections manager for Windows. The project was originally forked from the mRemote, and has been improved ever since. mRemoteNG allows you to view all of your remote connections in a simple yet powerful tabbed interface.
TrueCrypt
TrueCrypt is an open-source disk encryption tool for Windows XP, Windows Vista, Windows 8, Windows 10, Linux, and Mac OS X. With TrueCrypt, yo can encrypt an external storage device, such as a USB drive, or an entire hard disk on your PC. TrueCrypt has been discontinued since 2014.
GParted
GParted is a free and open source partition editor for graphically managing your disk partitions. With GParted you can resize, copy, and move partitions without data loss. The software enables you to grow and shrink your C: drive, create new space for operating systems and attempting data rescue from lost partitions on your hard drives.
TV-Browser
TV-Browser is an TV listings application that gets the daily TV program from the internet and shows it nativley in a neat user interface. The software runs on every system and platform with the Java runtime environment installed. With TV-Browser you can manage your TV listings your way, thanks to TV-Browser built in theming and plugin support.
OBS Studio
OBS Studio or Open Broadcaster Software is a free and open-source cross-platform streaming and recording program. The software is equipped with a powerful API that enbales extensions via Lua or Python written plugins and script to further customize the users experience and capabilities of OBS Studio. The open development of OBS Studio is funded with Open Collective, which enables the software to stay free and open.
Apache JMeter
Apache JMeter is an open source software Java-based load testing tool for analyzing and measuring the performance of a variety of services and applications. Apache JMeter uses Swing graphical API which means that it is not implemented by platform-specific coding. Developer use Apache JMeter to test performance both on static and dynamic resources, and simulate a heavy load on a server, group of servers, network or objects to test its strength or to analyze overall performance of applications.
PyTorch
An open-source machine learning framework designed and developed by Facebook's AI Research lab. With PyTorch, developers can build deep and machine learning models with ease, as the framework covers some of the most mundane parts of the process. PyTorch is released under a modified version of the BSD license and is totally free and open-source.
TensorFlow
TensorFlow is an end-to-end open source platform for machine learning. It has a comprehensive, flexible ecosystem of tools, libraries and community resources that lets researchers push the state-of-the-art in ML and developers easily build and deploy ML powered applications.