Qubes OS is a free and open-source security-oriented operating system meant for single-user desktop computing.
If I get it right, it runs apps on virtual machines for security reasons. That’s interesting, as I didn’t know about that. Qubes OS to me seems trade-free as I can install it without having to trade anything in return. I’d give them a small minus block, because of the promotion of trade-based networks on their website (twitter, linkedin, facebook). So 4/5 blocks.