Open Source Software for Windows
FreeCAD
FreeCAD is a highly customizable, scriptable and extensible computer aided design software software for the, MacOS, Linux and Windows operating systems. With FreeCad you can model and design real-life objects in 3D through parametric modeling where all 3D objects you design are controlled by parameters. FreeCAD is released as free and open source software under LGPv2+ license, and can be used for commercial and hobby projects alike.
HedgeDoc
HedgeDoc, formerly known as CodiMD is an open-source collaborative markdown editor. HedgeDoc provides collaborative features that makes it easy for teams to work together by creating notes, graphs and even presentations in real-time. With HedgeDoc, all you need to get started is to share a link to your co-workers, and they can join you in the process.
Remotely
Remotely is an all-in-one remote access software. With Remotely you can instantly connect to remote desktops either unattended or by invite, where invites are started from a single-file, portable executable that's easy for customers to download and use. Remotely also allow you to do remote scripting so that you can save time on quick fixes and ad-hoc scripting with an interactive console that lets you execute commands against multiple remote machines simultaneously, with instant results. Written with rich auto-complete for PowerShell Core, Windows PowerShell, Windows CMD, and Bash increases speed and accuracy of commands.
Swarmlet
Swarmlet is a free and open-source, self-hosted Platform as a Service that runs on any single server. It's mainly intended for use with multiple servers, a server cluster / swarm. Swarmlet is inspired by Dokku and brings the same simplicity to Docker Swarm. Swarmlet also uses Traefik v2 and Let's Encrypt to provide automatic SSL and load balancing on your apps.
neo4j
Neo4j is a commercially provided graph database management system developed by Neo4j, Inc. The graph database is fundamentally different to the relational model found in relational database management systems (RDBMS). With Neo4j, each data record, or node, stores direct pointers to all the nodes it's connected to. The database is also designed to perform complex queries with complex connections orders of magnitude faster. Neo4j is ACID-compliant and suited for projects that requires complicated relationship structures.
Unreal Engine
The Unreal Engine is a game engine and suite of tools and technologies developed by Epic Games. The engine was first released in 1998 as a part of the first-person shooter game Unreal, where the game itself was built on the engine. Today the Unreal Engine has grown into an ecosystem that includes a marketplace for game assets that can help indie developer to develop games and make a living selling game assets them selves. The Unreal Engine is free to use and provides a revenue-share model for developers and has been used to tipple A studios and indie developers to create games in almost every genre, including platformers, fighting games,RPGs, MMORPGs, and many more.
Sozi
Sozi is a free and open source, browser-based presentation software using SVG and JavaScript to create animated presentations. Unlike in most presentation applications, a Sozi document is not organised as a slideshow, but rather as a poster where the content of your presentation can be freely laid out. Playing such a presentation consists in a series of translations, zooms and rotations that allow to focus on the elements you want to show.
Ricochet
Ricochet is a communications application that uses the Tor network to reach your contacts without relying on messaging servers. It creates a hidden service, which is used to rendezvous with your contacts without revealing your location or IP address. Instead of a username, you get a unique address that looks like ricochet:rs7ce36jsj24ogfw.
Playnite
Playnite is an open source video game library manager that provides a unified interface for all of your games.
Docker
Docker is an open-source platform that automates deployment and development life cycles with OS-level virtualization. These virtualization are called containers and contain application specific operating system, software and configurations that are built on deployment. Containers are encapsulated and work across systems, be it in local development or on production servers, they run anywhere. Docker provides a Community Edition (CE) and an Enterprise Edition (EE) and can be used for personal and enterprise level projects alike.