NetBSD
NetBSD is a free, secure, and highly portable Unix-like Open Source operating system available for many platforms, from large-scale server systems to powerful desktop systems to handheld and embedded devices.
Its clean design and advanced features make it excellent in both production and research environments, and the source code is freely available under a business-friendly license.
Donations accumulated until 2021/12: 148.00 € (VAT included)
For each item you purchase, we donate part of our profits to The NetBSD Project. This way we all win :)
More information: http://www.netbsd.org/