From there, you’re free to take up pirating, smuggling, dogfighting, or trading, as you journey through the galaxy. As open-source games are continuously being tweaked and revised, many titles ...

It's free: no limitations, royalties or other fees apply. Nau Engine will always be free for any purpose, including commercial use. It's open: the entire source code is stored in a GIT repository.

and is free to use, but binary-only. (Editor’s note: the author was confused between the GPL open-source Qucs and the closed-source, binary-only QucsStudio. We’ve cleaned that up.) QucsStudio ...